# Optical Forums > Progressive Lens Discussion Forum >  Did you know this secrets:

## OCP

Everyone are talking about individualised lenses, vertex distance, Pantoscopic tilt etc, etc, but did you know that:
The Vertex distance have none (or lets say less) influence on the optical experience.The Pantoscopic tilt the same.The most important measure is the frame curve*Vertex*: Vertex distance is ONLY usefull if you measure the distance behind the eye examination equipment first, and then compare it with the vertex distance you measure with the new frame. It´s the difference that counts. At the same time the vertex distance is close to impossible to measure 100 % correct, and will only make a little power changing if the power is above 5 D.(if you manage to measure both measures correct)!!! Therefore this measure is not used at all from any manufacturer. A secret ? YES DEFINITE !

*Pantoscopic*: Close to be the same issue as above. You can measure 100 % correct angle, but only in the angle that the client want to stay in that day, so no manufacturer use this either, because no person stay with the same head angle all day..

*Frame curve*: This is important. Lets say VERY IMPORTANT. This measure will radically change the power when the frame is curved. But did you know that this actually is the only measure you need to take to make a perfect power compensated lens.? I guess not, because if you ask the industry they will claim you need to measure all three measures to make it individual. They only say this because the other does. Thats a fact.!

No matter what your supplier claims, this two measurements, Vertex and Pantoscopic, will only change power theoretical, and give not any optical improvements in real life. For the manufacturer this is a question of making the most individual and personalised lens out there, but lets get our feet on ground again. With all these measures we are only getting confused and we all think we do it so damn great by measure all these data. And for NO reason. THATS THE TRUTH.!
Have a nice Christmas everyone, and sorry for my school english.:finger:

Mike (Shamir wholesaler)

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## AWTECH

> The Vertex distance have none (or lets say less) influence on the power.The Pantoscopic tilt the same.The most important measure is the frame curve*Vertex*: Vertex distance is ONLY usefull if you measure the distance behind the eye examination equipment first, and then compare it with the vertex distance you measure with the new frame. It´s the difference you can use. At the same time this measure is close to impossible to measure 100 % correct, and will only make a little power changing if the power is above 5 D.!!! Therefore this measure is not used at all from any manufacturer. A secret ? YES DEFINITE !
> 
> *Pantoscopic*: Close to be the same issue as above. You can measure 100 % correct but only with the angle the client stay in that day, so no manufacturer use this either.
> 
> *Frame curve*: This is very important. Lets say VERY IMPORTANT. This measure will radically change the power when the frame is curved. But did you know that this actually is the only measure you need to take to make a perfect power compensated lens.? I guess not, because if you ask the industry they will claim you need to measure all three measures to make it individual. They only say this because the other does. Thats a fact.!
> 
> No matter what your supplier claims, this two measurements, Vertex and Pantoscopic, will only change power theoretical, and give not any optical improvements in real life. For the manufacturer this is a question of making the most individual and personalised lens out there, but lets get down on earth again. With all these measures we are only getting confused and we all think we do it so damn great by measure all these data. And for NO reason. THATS THE TRUTH.!
> Have a nice Christmas everyone, and sorry for my school english.:finger:
> 
> Mike (Shamir wholesaler)


This is a very accurate statement regarding position of wear. 

I would just like to add that the individualization of the height of the add relative to the distance optical  center can vary for each frame by any amount the software designer chooses, but the patient who has been wearing a progressive lens is going to have his eye and brain expect the add to come into full power at about the same distance as before.  So if the patient has been wearing a frame with 26mm B and a fitting height of 18mm.  The optical center of the standard PAL would be about 2 mm above the bottom of the B measurement.  Now if they select a sunlens that is an aviator shape with a B measurement of 38mm and the fitting height is now 30mm for example.  Some lens design may optimize this to extend the corridor and the optical reading center to be their longest.  This may increase the corridor length from 13mm to 17mm or 4mm more eye movement required when they switch from one to the other.

There is alot that can be done to individualize but what is practical, and what can properly explained so true improvements are delivered.

Some of these new possiblities have greater risks than rewards.

Example: Online ordering by the optician takes out one great previous remake reason.  The person calling in the job or the person writing it down at the lab made a simple error.  Each time you eleminate the possiblity for an error the better.  Is the gain with some of this individualization really worth it?

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## THE MEB

I agree wholeheartedly with the comments regarding vertex distance, and pantoscopic tilt, especially for myopes, have no large effect in the patient seeing better. I have been fitting glasses for 35 years, and it's been my  experience, practically speaking, that the major improvement that can be made to help the patient see better is changing the frontal bow of the frame to accomadate their rx.
   With myopes, I have found that the flatter the frontal bow, the more clearly the patient sees. Conversly, with hyperopes, the more frontal bow given the more clearly they see. Also, it seems, that typically hyperopes prefer more pantoscopic tilt than myopes.
   Of course these finding are just generalizations, but it has been my experience that the more myopic or hyperopic a patient is, the better the results of changing the curve of the front of the frame becomes. I have also seen the opposite of what I described holds true as well, but very rarely.
   The point being, the first thing I try to do, if the patient is not seeing clearly out of their new rx, and you have already checked to see if rx and seg heights etc.. are lined up properly, is to alter the frontal bow of the frame. I have found this to be a huge help through the years.

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## cocoisland58

> The point being, the first thing I try to do, if the patient is not seeing clearly out of their new rx, and you have already checked to see if rx and seg heights etc.. are lined up properly, is to alter the frontal bow of the frame. I have found this to be a huge help through the years.


True and in fact a little bit of everything might help but the frontal curve makes the most difference. Always check against their old frame.  You know how often someone is wearing an extreme flat or an extreme curve on their old frame simply because of them being bent over the years and they have adapted.

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## OCP

> Example: Online ordering by the optician takes out one great previous remake reason. The person calling in the job or the person writing it down at the lab made a simple error. Each time you eleminate the possiblity for an error the better. Is the gain with some of this individualization really worth it?


This is very true. The suppliers want us to take all these measures, and everytime they ask you to take a new measure, you will only increase the risk of errors.
In my opinion (as Shamir wholesaler) we recommend our customer when they order Auto II, only to measure the Faceform angle (the curve of the frame) with the Panorameter, Vertex in 13 mm (just to write something and to let the software accept the order) and for the Pantoscopic tilt choose 9 if the frame looks normal to the cheek, 12 if it´s very obliqe angle, and 5 if its a very vertical angle to the cheek. We don´t recommend to measure the Pantoscopic tilt with the Panorameter or others, but only visuel consider which angle to order. It´s impossible to measure the Pantoscopic tilt correct with any equipment. Only the front curve of the frame is a stationary measure that will not change.

Mike

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## AWTECH

> This is very true. The suppliers want us to take all these measures, and everytime they ask you to take a new measure, you will only increase the risk of errors.
> In my opinion (as Shamir wholesaler) we recommend our customer when they order Auto II, only to measure the Faceform angle (the curve of the frame) with the Panorameter, Vertex in 13 mm (just to write something and to let the software accept the order) and for the Pantoscopic tilt choose 9 if the frame looks normal to the cheek, 12 if it´s very obliqe angle, and 5 if its a very vertical angle to the cheek. We don´t recommend to measure the Pantoscopic tilt with the Panorameter or others, but only visuel consider which angle to order. It´s impossible to measure the Pantoscopic tilt correct with any equipment. Only the front curve of the frame is a stationary measure that will not change.
> 
> Mike


You have developed an excellent yet simple method for Panto and if they are off by 2 degrees the compensation will be insignificantly changed.  We use 13.5 mm vertex as our default. (and 0.5mm will have almost no change to the prescription or the number).

The big advantage to a device for patient measurement will be to show the patient how high tech and individualized the measurements are compared to how they have always been previously fitted.

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## YrahG

Panto and Faceform have the very same effect on the prescription. In a PAL since we have a narrow corridor the design of the lens can benefit from the faceform measurements becuase the same degree of panto is only going to move the reading area higher or lower where as the faceform will narrow the corridor. This thread is the exact reason why the need to know if the effect panto and face is taken into consideration into both the prescription and the design. 

The very same thing can be said about FF lenses compared to conventional lenses. If we are to pursuit precision we shoudn't set caps or ceilings on ourselves.

I remember when opticians used to teach each othr to fit certain lenses 1mm lower or 1mm higher instead of avoiding the design if it did not work for that patient.

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## AWTECH

YrahG said:


> The very same thing can be said about FF lenses compared to conventional lenses. If we are to pursuit precision we shoudn't set caps or ceilings on ourselves.


We also have to be careful to not setup measuring and other detailed specifications that can not be followed by the majority of opticians, or we need to have an industry standard. Or each company would have their own method to determine which opticians were approved to take measurements that the majority of opticians were likely not be able to obtain correctly.

As an example of the difficulty in requiring measurements that are not the daily standard, we still have a problem getting the majority of optician, many of whom are very good and skilled into sending an optical center height for a single vision lens.  (They expect you to split the B measurement, which works great for a round Ben Franklin style of frame but not very well for a fashion wrap)

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## Barry Santini

> Everyone are talking about individualised lenses, vertex distance, Pantoscopic tilt etc, etc, but did you know that:
> The Vertex distance have none (or lets say less) influence on the optical experience.The Pantoscopic tilt the same.The most important measure is the frame curve*Vertex*: Vertex distance is ONLY usefull if you measure the distance behind the eye examination equipment first, and then compare it with the vertex distance you measure with the new frame. It´s the difference that counts. At the same time the vertex distance is close to impossible to measure 100 % correct, and will only make a little power changing if the power is above 5 D.(if you manage to measure both measures correct)!!! Therefore this measure is not used at all from any manufacturer. A secret ? YES DEFINITE !
> 
> *Pantoscopic*: Close to be the same issue as above. You can measure 100 % correct angle, but only in the angle that the client want to stay in that day, so no manufacturer use this either, because no person stay with the same head angle all day..
> 
> *Frame curve*: This is important. Lets say VERY IMPORTANT. This measure will radically change the power when the frame is curved. But did you know that this actually is the only measure you need to take to make a perfect power compensated lens.? I guess not, because if you ask the industry they will claim you need to measure all three measures to make it individual. They only say this because the other does. Thats a fact.!
> 
> No matter what your supplier claims, this two measurements, Vertex and Pantoscopic, will only change power theoretical, and give not any optical improvements in real life. For the manufacturer this is a question of making the most individual and personalised lens out there, but lets get our feet on ground again. With all these measures we are only getting confused and we all think we do it so damn great by measure all these data. And for NO reason. THATS THE TRUTH.!
> Have a nice Christmas everyone, and sorry for my school english.:finger:
> ...


I'm not sure I completely agree with all the above.

IMHO, Panto really comes into its own in a progressive lens, where it helps define the visual axis obliquity in the near zone.

Some whole lens optimization programs, I believe, help correct/reduce unwanted astigmatism in the near zone with large deviations in panto value from the norm range, and also employ VD to further iterate the result.

And, if frame curve was realy so important, as you say (and I'm not saying it isn't, but since your kinda speaking from Shamir's viewpoint), then why does Auto II SV POW FF range allow up to 15 degrees of FF, with no POW compensation for the same in evidence?

To the best of my knowledge...and I certainly could stand to be corrected here....

B

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## YrahG

> YrahG said:
> 
> We also have to be careful to not setup measuring and other detailed specifications that can not be followed by the majority of opticians, or we need to have an industry standard. Or each company would have their own method to determine which opticians were approved to take measurements that the majority of opticians were likely not be able to obtain correctly.
> 
> As an example of the difficulty in requiring measurements that are not the daily standard, we still have a problem getting the majority of optician, many of whom are very good and skilled into sending an optical center height for a single vision lens. (They expect you to split the B measurement, which works great for a round Ben Franklin style of frame but not very well for a fashion wrap)


I agree it'snot for the faint of heart, but I would ventue to say that the number of opticians sending in this data now is very small.  Even I myself will leave these figures out in low powers.

A traditional lens assumes a panto of roughly 10 to 15 degrees and a face of 5 to 8 degrees.  There exists a rule of thumb where we should lower the OC 1mm fro every 2 degrees of panto and this would allow us to not compensate the prescription.  It used to be that a properly fit frame would have roughly 5 to 8 degrees of faceform and decentration of 2 to 3mm per eye.  That wrap and that decentration go hand in hand.  The need for compensations exists because opticians don't follow good fitting procedures anymore, frame manufacturers make frames that cannot have panto adjusted, and many other factors.  As worn has become a method of correcting mistakes our industry has created and the measure of the variables to provide precision eyewear will be a tool best used by the brighter opticians, but I wouldn't call it unnecessary.

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## AWTECH

If you read all of the opinions in various post by many different optical professionals, you will see there are many different opinions.

I believe at some point you have to accept the manufacturers required information and procedures and follow them, if you don't get the patient satisfaction you are expecting it will probably be better to just find another supplier who you can work with.

If you can't trust the lens design specifications, rules, and recommendations, I don't think trying to add individualized tweeks to the supplied data will deliver a better lens for the patient.  In fact these tweeks are likely to cause problems as only one suspected aspect has been addressed and this information is all related to all of the other required information.  The possiblity for errors is increased due to the significance of the order of the various math formulas usage and the resulting compensation can be changed by using any substitute provided data that is not recommended by the supplier.

Another source for potential error is the lab management system and the interface with the lens calculation software.  Unless the correct exchange of this information happens there is real possiblity that one lab management system might produce a lens design slightly differently than another.  This is a great challenge for the lens companies as they try to distribute lens design software to work with different software and hardware platforms.

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## YrahG

> If you read all of the opinions in various post by many different optical professionals, you will see there are many different opinions.


To each there own, this is a great place to share the things we learn and tweak our opinions to create a uniform truth.




> I believe at some point you have to accept the manufacturers required information and procedures and follow them, if you don't get the patient satisfaction you are expecting it will probably be better to just find another supplier who you can work with.


Great and wise statement, a one size fits all philosophy never worked for me.  I like to have a few progressive designs in my arsenal.




> If you can't trust the lens design specifications, rules, and recommendations, I don't think trying to add individualized tweeks to the supplied data will deliver a better lens for the patient. In fact these tweeks are likely to cause problems as only one suspected aspect has been addressed and this information is all related to all of the other required information. The possiblity for errors is increased due to the significance of the order of the various math formulas usage and the resulting compensation can be changed by using any substitute provided data that is not recommended by the supplier.


This is the truth, everytime the optician or fitter uses a tweak the design has been comprimised.  Better to move on, too many good designs out there to try the one size fits all method.




> Another source for potential error is the lab management system and the interface with the lens calculation software. Unless the correct exchange of this information happens there is real possiblity that one lab management system might produce a lens design slightly differently than another. This is a great challenge for the lens companies as they try to distribute lens design software to work with different software and hardware platforms.


Communications standards exist, now how each manufacturer implements them and which proprietary procedures they implement are a different story.  That's where things will differ by lab, some will invest int he top of the line to ensure great products are produced consistently, others will go for the cheap equipment just to use the FF buzzword.  This is the foundation of a good FF offering through any ECP's office determining who is willing to invest in this technology and who's just exploiting it.  I use a lab that invests in this technology, I have seen their equipment first hand and know it is some of the best, I have also seen their commitment to perfection in the QC department, this is where I am the most interested.  Once again I know that the design is not the labs it belongs to the manufacturer, the QC is the key to ensureing that my trust in the manufacturers design was delivered by my lab.

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## Darryl Meister

> Pantoscopic tilt etc, etc, but did you know that: 
> The Vertex distance have none (or lets say less) influence on the optical experience.The Pantoscopic tilt the same.The most important measure is the frame curve


Unfortunately, I think you have been misinformed. Several of the points made in this post are not entirely accurate. To assert that the company you are affiliated with, Shamir, only utilizes position of wear measurements for _prescription compensation_ is one thing. I completely agree that prescription compensation offers only minimal visual benefit to the wearer, as I have described ad nauseam in other threads, including this post from just a few days ago.

But the assertion that position of wear measurements do not influence optical performance, or that _other_ lens manufacturers do not utilize these measurements when designing and fabricating free-form lenses, is incorrect. The position of wear can significantly influence optical performance over the entire lens design in many cases.

Basic prescription compensation, on the other hand, only improves vision through a narrow region of the distance zone. Further, any eye care professional can apply this form of prescription compensation to any lens, even semi-finished, using free software tools.

I have included an actual optical comparison of three different lenses, which demonstrates the influence of the position of wear. I would also encourage you to review US Patent 6,089,713, which details the use of position of wear measurements when calculating free-form lens designs.




> Vertex distance is ONLY usefull if you measure the distance behind the eye examination equipment first, and then compare it with the vertex distance you measure with the new frame. It´s the difference that counts


This, again, refers to the same type of prescription compensation that eye care professionals have been applying for years. Free-form lens designs that are truly customized for the position of wear, on the other hand, utilize the vertex, or _stop_, distance to perform optical ray tracing of a lens-eye model in the position of wear. This is completely independent of any vertex compensation applied because of differences between the refracted and fitted vertex distances.




> Frame Curve... This measure will radically change the power when the frame is curved


Actually, for a given base curve, the curvature of the frame can only influence optical performance by changing the _position of wear_, since decentering a meniscus lens introduces lens tilt. Otherwise, the curvature of the frame has no more effect upon optical performance than the color of the frame.

Now, if you have chosen to _substitute_ a steeper or flatter base curve in lieu of the manufacturer's recommended base curve to achieve a better fit in a frame, thereby violating "best form" optical principles, sufficiently advanced free-form lens designs with full optical optimization can apply the necessary optical corrections over the lens surface.




> If you read all of the opinions in various post by many different optical professionals, you will see there are many different opinions.


But, sadly, the _opinions_ often expressed on the Internet do not represent _facts_. Nevertheless, it would be nice to keep the flow of "disinformation" to a minimum.

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## YrahG

> Unfortunately, you have been misinformed. Most of the points made in this post are incorrect. To assert that the company you are affiliated with, Shamir, only utilizes position of wear measurements for _prescription compensation_ is one thing. I completely agree that prescription compensation offers only minimal visual benefit to the wearer, as I have described ad nauseam in other threads, including this post from just a few days ago.
> 
> But the assertion that position of wear measurements do not influence optical performance, or that _other_ lens manufacturers do not utilize these measurements when designing and fabricating free-form lenses, is completely false. The position of wear can significantly influence optical performance over the entire lens design.
> 
> Basic prescription compensation, on the other hand, only improves vision through a narrow region of the distance zone. Further, any eye care professional can apply this form of prescription compensation to any lens, even semi-finished, using free software tools.
> 
> I have included an actual optical comparison of three different lenses, which demonstrates the influence of the position of wear. I would also encourage you to review US Patent 6,089,713, which details the use of position of wear measurements when calculating free-form lens designs.
> 
> 
> ...


Thank you for the patent reference and the reiteration of the differences between prescription and design. I think your software (spectacle optics) makes it not only posible to compensate lenses but the tschernings ellipse makes it possible to see the effects of vertex on best form.

I also don't think that Shamir would endorse the roiginal posters statements.  I have worked in a lab in the past but it did not make me that much more knowledgeable about the product, I think in the case of FF this effect is multiplied to an even greater extent.

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## Darryl Meister

> I think your software (spectacle optics) makes it not only posible to compensate lenses but the tschernings ellipse makes it possible to see the effects of vertex on best form.


Yes, good point. Although it will not demonstrate the complex optical interaction between position of wear aberrations and the astigmatism of a progressive lens surface, the Optical Analysis module will also allow you to see the effects of viewing angle and vertex distance on optical performance (Spectacle Optics thread).

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## YrahG

I wish more education existed so that it wasn't so that opticians weren't considered the low hanging fruit. Misinformation is how some will make their money.

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## OCP

> Unfortunately, I think you have been misinformed. Several of the points made in this post are not entirely accurate. To assert that the company you are affiliated with, Shamir, only utilizes position of wear measurements for _prescription compensation_ is one thing. I completely agree that prescription compensation offers only minimal visual benefit to the wearer, as I have described ad nauseam in other threads, including this post from just a few days ago.
> 
> But the assertion that position of wear measurements do not influence optical performance, or that _other_ lens manufacturers do not utilize these measurements when designing and fabricating free-form lenses, is incorrect. The position of wear can significantly influence optical performance over the entire lens design in many cases.
> 
> Basic prescription compensation, on the other hand, only improves vision through a narrow region of the distance zone. Further, any eye care professional can apply this form of prescription compensation to any lens, even semi-finished, using free software tools.
> 
> I have included an actual optical comparison of three different lenses, which demonstrates the influence of the position of wear. I would also encourage you to review US Patent 6,089,713, which details the use of position of wear measurements when calculating free-form lens designs.
> 
> 
> ...


Hi Darryl

Sometimes it´s better to overstate the facts to get people understand, but it will not change the point, that Vertex and Panto is more or less impossible to measure correct and are an surce to errors. I see measurement of 15 degrees pantoscopic, when the real measure should be 7. You know just as well as I do, that this could very well be the reasson that the lenses don´t fit prober, and when the client have issues with their new and expensive glasses, you and I (read Zeiss and Shamir)got the problem. My statement is my own opinion offcause, but it will not change the meaning of the contence. Some opticians cant get the personalised lenses like Auto II, the Individual, or the Impression to fitt perfect every time, and I´m quite sure it´s not in the lenses we find the problem, but in the measurements taking by the opticians. To bring down my statement back to reality again, I still think we would all have better lenses by ignoring Vertex and Pantoscopic, or at least use only three different degrees of pantoscopic like 5, 9 or 12 degrees. -and you know just as I do, that you cant use Vertex for anything if you dont got the differences between the refracted and fitted vertex distances. And when do optician take these measures at all, and do you have any guarantee that this measure has been taking 100 % correct? I guess not, and therefore you got an extra surce for mistakes, just like the pantoscopic tilt.

This is my statement and how it works in real life experience. This is different theoretical, but I´m quite sure Shamir and others would agree in real time experience.

Mike

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## Barry Santini

Mike:

I'm not sure why you feel that it's OK to use a set a default pre-set values for Panto (like 5,9, & 12) but it's *not* OK to use an already-substantiated value range of 12.5 to 14.5mm as OK for use as default values (say 13.5mm, yes?) in refractions done with a phoroptor.

I suspect that, as a value, 13.5mm is closer to what would normally be measured in the exam room than what's measured currently with panto at the dispensing desk.

What do you think?

Barry

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## Darryl Meister

> Sometimes it´s better to overstate the facts to get people understand


I think your post might be interpreted more as _misrepresenting_ the facts, not _overstating_ them, particularly when you are making some rather specific claims followed by assertions that they are "facts" and "true."




> but it will not change the point, that Vertex and Panto is more or less impossible to measure correct and are an surce to errors. I see measurement of 15 degrees pantoscopic, when the real measure should be 7.


Your main point was that these mesaurements do not matter in the first place, which is not accurate. It may be more difficult to take some of these measurements accurately using common dispensing tools, like a PD ruler, but consider the following:

1. Taking position of wear measurements to the best of your ability is still better than not considering these measurements at all, just as taking a less than accurate PD measurement is preferable to using some average value for every single person.

2. There are both manual and digital centration tools available that can take sufficiently accurate position of wear measurements. For that matter, the old "distometer" can take very accurate vertex distance measurements.




> Auto II


According to your post, your company's Autograph II lens is not fully customized for the position of wear anyway, which would exclude it from the class of lenses including ZEISS Individual and Rodenstock Impression ILT.




> at least use only three different degrees of pantoscopic like 5, 9 or 12 degrees.


That's still better than not measuring them at all and will still only matter if your free-form lens actually takes these measurements into account when calculating the lens design for the patient.




> and you know just as I do, that you cant use Vertex for anything if you dont got the differences between the refracted and fitted vertex distances


Again, you are referring to compensation of the prescripton for the vertex distance. While this can be applied _in addition_ to any design modifications based upon the vertex distance, I am referring to the design modifications.

Think of it like this: Suppose you are looking through some point on the lens at 15 mm from the center. Now, at a vertex distance (_refracted and fitted_) of 13.5 mm, this represents an angle of view of 29.1 degrees, assuming that the center of rotation is another 13.5 mm behind the corneal apex. Now, if you shorten the vertex distance from 13.5 to 7.5 mm, you would be looking through the same point at an angle of 35.5 degrees, which represents a change in the "tilt" of the line of sight relative to the lens of almost 6.5 degrees.

It gets a little more complicated depending upon the initial tilt and curvature of the back lens surface relative to the line of sight, but you should at least see from this example that differences in vertex distance, with or without compensation, can influence oblique astigmatism calculations away from the center of the lens. This is why the near zone in my earlier graphical comparison is "closed off" with unwanted astigmatism compared to the distance zone.

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## OCP

> Mike:
> 
> I'm not sure why you feel that it's OK to use a set a default pre-set values for Panto (like 5,9, & 12) but it's *not* OK to use an already-substantiated value range of 12.5 to 14.5mm as OK for use as default values (say 13.5mm, yes?) in refractions done with a phoroptor.
> 
> I suspect that, as a value, 13.5mm is closer to what would normally be measured in the exam room than what's measured currently with panto at the dispensing desk.
> 
> What do you think?
> 
> Barry


 
Hi Barry

What I suggest is to measure the Panto tilt by VISUEL valuation. If the tilt is very oblique select 12, if it´s very vertical use 5, and if it looks normal tilt to the cheek select 9. This is because this tilt is very difficult to measure and because it´s not an fixed measure. It depends on how the person is standing, and therefore I suggest you measure this value visuel. Of cause you cant measure 100% correct this way, but you cant measure this value 100% correct anyway, so it´s an question of ordering realistics as possible.

About the Vertex you need to announce the refracted vertex AND the fitted vertex, because it´s the difference between these two values that makes the pow. comp. BUT it only makes a difference if the power is above 5D and it will only give optical improvement if you measure both values 100% correct, and that is nearly impossible. If your power is -6D and you measure 2 mm wrong, the lenses will NOT work. It´s very easy to measure 2 mm wrong in difference.

The Vertex distance does not change power so much. You can see the difference when you put an client from -3 glasses to contakt lenses. How much does the power change? Maximum 0,25 D in *13* mm difference!!!
The difference between the refracted Vertex and the Fitted Vertex lets say this is only 2 mm. How much would the power change then? I tell you. Aprox. 0,04 D !!! So the Vertex value is in the most cases an theoretical improvement.!!

*So, if you do order vertex in 13,5 mm, the supplier does not use this value at all, because they need the refracted value as well to find the difference!*

For Darryl. I read and understand your point, but this is still what I claim is "theorethical" improvement. How Zeiss, Shamir or Rodenstock are handling the abberations (because this is actually what we are talking about here) is secrets, and we have all different philosophyes how to handle this. When you exclude the Auto II from the group of individual lenses like Individual, I thank you for that, because we actually think that we are steps ahead these products with Auto II. So your right about this. :bbg:
Shamir are calculating the Vertex and Panto values just as other suppliers does, but that still dont change the statement that it´s sometime unnecessary values.

I hope this could clear out some statements.

Mike

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## D.J. Roff, ABOM

I will have to agree with the original comment, as to the vertex measurement being the least critical.  Obviously, we can determine a mathmatical power variance when the vertex is not what the doctor used at the phoropter, but unless the patient has an EXTREMELY high Rx (more than +/-10.00), this rarely comes into play.  And the concern with progressive fit is the same with an "individual" lens design as it was with an Omni:  the patient wearing it on the end of their nose is like trying to see through a keyhole into a room, with their eye a foot from the door.  This is simple common sense, although we're still explaining it to some patients.  And no matter how well-fit the lens is, I guarantee it will refuse to sit at the same vertex, plus-or-minus 0.5, for the lifetime of the glasses, just because we wow the patient with our distometer.

The importance of pantoscopic tilt in a progressive fit, however, should not be underestimated.  I have had many patients come in with adaptation problems where that one adjustment made all the difference... often saving a non-adapt or even a refund.  The patient's near viewing angle, while certainly not static throughout their day, _can_ be approximated, and is an issue of very individual sensitivity... just like "faceform", or "bow" in the frame front.  I try to match both of these values to whatever the patient has accommodated to.  How well I do will determine how comfortable the patient is with their correction, in many cases... regardless of what lens design I'm fitting.

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## Darryl Meister

> *So, if you do order vertex in 13,5 mm, Zeiss and other does not use this value at all, because they need the refracted value as well to find the difference!*


Once again, you are misrepresenting facts. ZEISS Individual does indeed use the vertex distance in the lens design calculations, as I have already described in detail. Feel free to order and plot two Individual lenses with different vertex distances to see this for yourself. I would recommend doing this before you make further erroneous statements in a public forum.

Please refer to my previous posts, which explain the difference between power compensation for the vertex distance and lens design modifications based upon the vertex or assumed "stop" distance. ZEISS Individual has the entire design modified based upon this distance.




> When you exclude the Auto II from the group of individual lenses like Individual, I thank you for that, because we actually think that we are steps ahead these products with Auto II. So your right about this. :bbg: Shamir are calculating the Vertex and Panto values just as other suppliers does, but that still dont change the statement that it´s sometime unnecessary values


You stated in your original post that Shamir's lens designs _do not_ rely on position of wear measurements. If by ignoring these measurements you believe that Autograph II is _more advanced_ than products that perform the extensive calculations necessary to do this, I would say that you are certainly entitled to your opinion, even if I do not agree with it.

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## AWTECH

All of these measurements, are important but to what degree?

Consider wavefront lens designs, it is not pratical for a lens to be used in a frame but can be used for contacts.  In a contact for example a off axis of 3 degrees can cause the lens to not work. (The eye certainly moves more than 3 degrees).

How do place a frame back in the same position on the face. (not by the optician but the actual everyday user?)  How close can the optician fit the frame to the face each time?

This brings up the point of designing a lens not just for maximum optical performance in a lab but one that will work in the real world.

I believe this tread was started in an attempt to show what is working in the real world use not just in theory.

Does an optimized surface of a lens work when it is mounted 0.5mm wrong by the lab? (I know it shouldn't be, but again real world) etc., etc., etc.

No one wants to wear that frame that is attached to the skull with special titanium screws to guarantee exact position of wear.

Just a few thoughts on the subject to consider.

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## Darryl Meister

Mike, I do not want to come across in this thread as combative or argumentative. And I do not want to discourage you from sharing your thoughts with the rest of the members of OptiBoard as much as possible. My intention in these last few posts has only been to clarify certain claims that you are making regarding products that I happen to be intimately familiar with, like Zeiss Individual, as a guy who spends much of his day calculating and analyzing them.
:cheers:

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## OCP

> Once again, you are misrepresenting facts. ZEISS Individual does indeed use the vertex distance in the lens design calculations, as I have already described in detail. Feel free to order and plot two Individual lenses with different vertex distances to see this for yourself. I would recommend doing this before you make further erroneous statements in a public forum.
> 
> Please refer to my previous posts, which explain the difference between power compensation for the vertex distance and lens design modifications based upon the vertex or assumed "stop" distance. ZEISS Individual has the entire design modified based upon this distance.
> 
> 
> You stated in your original post that Shamir's lens designs _do not_ rely on position of wear measurements. If by ignoring these measurements you believe that Autograph II is _more advanced_ than products that perform the extensive calculations necessary to do this, I would say that you are certainly entitled to your opinion, even if I do not agree with it.


Well, as I have already told, Shamir are calculation the values just like anyone else. BUT that does still not change my personal stance on this.
I did not put down Zeiss or other products, just told you my personal opinion on how to handle these issues and misunderstandings of these two values, and what is theoretichal and what is practical. You do not agree in my statement, and that way we got an constructive debate.

Mike

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## Darryl Meister

> Does an optimized surface of a lens work when it is mounted 0.5mm wrong by the lab? (I know it shouldn't be, but again real world) etc., etc., etc


I've never really understood the merits of this argument, which seems akin to OCP's argument. Optically customized lenses seek to preserve the intended optical performance of the lens design, regardless of the prescription and/or position of wear.

Consider your own scenario: A frame initially fits the patient with 12 degrees of pantoscopic tilt. You measure it at 10 degrees of panto. Your patient puts the frame on the next day, higher on the bridge of the nose, so it is now at 9 degrees of panto. Does this mean that the lens suddenly stops working compared to a lens that is not optimized for the position of wear at all? Of course not. You are still 9 degrees closer to providing the intended optical performance than you would have been.

That said, I want to reiterate the fact that I completely agree that free-form lens suppliers only compensating the prescription for the position of wear, and not modifying the actual lens design, are not delivering meaningful visual improvements any many prescriptions, simply because the optical differences involved are indeed quite small.

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## OCP

delete

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## Darryl Meister

> You show two plots with +3 D in two different vertex distance and with different design. BUT you did not told us the refracted vertex on the first plot.? If the refracted vertex for both designs is 7,5 mm, the plot will natural be different, because the power comp. would make the shorter vertex with stronger power.!


1. All three lenses in the comparison use the exact same lens design.

2. All three lenses were calculated to provide a +3.00 D at the specified vertex distance, so there is _no difference_ in power between the refracted and fitted vertex distance.

3. Yes, the lenses look different anyway, as I have been saying all along. ;)

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## OCP

> 1. All three lenses in the comparison use the exact same lens design.
> 
> 2. All three lenses were calculated to provide a +3.00 D at the specified vertex distance, so there is _no difference_ in power between the refracted and fitted vertex distance.
> 
> 3. Yes, the lenses look different anyway, as I have been saying all along. ;)


 
Hi Daryl.

Okay back to my statement that Vertex is more theoretical than optical noticeable improvement, and still most opticians cant measure both vertex values correct. Anyway. Does you have an power plot? 

Annoying Mike

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## Mr. Finney

> This is because this tilt is very difficult to measure and because it´s not an fixed measure. It depends on how the person is standing, and therefore I suggest you measure this value visuel. Of cause you cant measure 100% correct this way, but you cant measure this value 100% correct anyway, so it´s an question of ordering realistics as possible.


Just FYI, my glasses have the same panto angle whether I'm sitting, standing, lying down, watching TV, taking a shower, etc.  




> About the Vertex you need to announce the refracted vertex AND the fitted vertex, because it´s the difference between these two values that makes the pow. comp. BUT it only makes a difference if the power is above 5D and it will only give optical improvement if you measure both values 100% correct, and that is nearly impossible.


That's actually quite a ridiculous statement to make.  So if I measure both values only 98% correct, there won't be ANY optical improvement?  Wouldn't the improvement depend on how far from the mean values my measurements were, assuming my measurements were closer to perfect than the mean?




> If your power is -6D and you measure 2 mm wrong, the lenses will NOT work. It´s very easy to measure 2 mm wrong in difference.


So a power of -6D will work, but a power of -5.93D or -6.07D won't work?  Because that's the diference you're talking about.  Which points out that both viewpoints are correct.  Vertex power compensation doesn't make that big of a difference, but why shouldn't we attempt to get things as close to perfect as we can?




> The Vertex distance does not change power so much. You can see the difference when you put an client from -3 glasses to contakt lenses. How much does the power change? Maximum 0,25 D in *13* mm difference!!!
> The difference between the refracted Vertex and the Fitted Vertex lets say this is only 2 mm. How much would the power change then? I tell you. Aprox. 0,04 D !!! So the Vertex value is in the most cases an theoretical improvement.!!


So what you're saying, just as Darryl and others have said, is that power compensation, not design compensation, for vertex distance, is not a big factor.  Right?  We all get that.

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## Barry Santini

You know, I actually consulted our great DM on this whole question of panto. And I think Laurie S also chimed in before and helped to cleared it up:

You appropriately measure pantoscopic tilt by first ensuring the the client's "facial plane"., i.e. head plane (Try drawing a line across the upper and lower orbital bones, and further iterate with the dental plane of the mouth and the chin) is as straight up & down as possible.

(I think someone in Texas, in the 1970's made a series of "proscopic heads" to help train dispeners how to fit and measure eyewear).

WITH THE CLIENT'S HEAD IN THIS "ORTHOGONAL" POSITION, USE THE ZEISS PANTO PLUMB (OR SIMILAR DEVICE) AND ASCERTAIN THE TILT OF THE ALREADY PRE-FITTED EYEWEAR.

It's doesn't matter after that if they habitually tilt their head forward or backward (except with respect to pupil height position).

This then, is the pantoscopic angle the designers are looking for in order to perform their optimizations.

And I'm still open to being further corrected here.

Barry

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## Darryl Meister

Yes, as long as you have measured the pantoscopic angle of the frame with the line of sight passing through the intended fitting point on the lens, head tilt no longer matters, at least as long as you have measured the fitting height correctly.

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## AWTECH

> You know, I actually consulted our great DM on this whole question of panto. And I think Laurie S also chimed in before and helped to cleared it up:
> 
> You appropriately measure pantoscopic tilt by first ensuring the the client's "facial plane"., i.e. head plane (Try drawing a line across the upper and lower orbital bones, and further iterate with the dental plane of the mouth and the chin) is as straight up & down as possible.
> 
> (I think someone in Texas, in the 1970's made a series of "proscopic heads" to help train dispeners how to fit and measure eyewear).
> 
> WITH THE CLIENT'S HEAD IN THIS "ORTHOGONAL" POSITION, USE THE ZEISS PANTO PLUMB (OR SIMILAR DEVICE) AND ASCERTAIN THE TILT OF THE ALREADY PRE-FITTED EYEWEAR.
> 
> It's doesn't matter after that if they habitually tilt their head forward or backward (except with respect to pupil height position).
> ...


I agree with you this is a proper way to measure panto, but my concern is limited number of opticians that know how to do this.  Some will just not get it, remember supplying lenses we are dealing with a very few knowledgable opticians and also alot of people selling lenses who the day before they were an optician there business lingo was, "would you like fries with that order".   In many cases as was originally stated the method suggested may produce a more satisfied patient than a poorly trained and educated craftsman with an excellent tool.  

I will even go so far as to say Barry you could probably take a known frame fitted to an unseen patient, (Thats right one you have never even met or seen a picture of), and supply a better estimated panto than a poorly trained dispenser with a fancy panto tool.

I have expressed my concerns before and suggested the best approach maybe to only offer such customized fitting by approved and trained opticians. (This idea will fair when discussed with the Sr. VP of sales)

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## Mr. Finney

> I agree with you this is a proper way to measure panto, but my concern is limited number of opticians that know how to do this.  Some will just not get it, remember supplying lenses we are dealing with a very few knowledgable opticians and also alot of people selling lenses who the day before they were an optician there business lingo was, "would you like fries with that order".   In many cases as was originally stated the method suggested may produce a more satisfied patient than a poorly trained and educated craftsman with an excellent tool.  
> 
> I will even go so far as to say Barry you could probably take a known frame fitted to an unseen patient, (Thats right one you have never even met or seen a picture of), and supply a better estimated panto than a poorly trained dispenser with a fancy panto tool.
> 
> I have expressed my concerns before and suggested the best approach maybe to only offer such customized fitting by approved and trained opticians. (This idea will fair when discussed with the Sr. VP of sales)


We could always let the so-called "opticians" poorly dispense lenses, then the customers will go to actual Opticians, who will dispense lenses that the customers can actually see well with, and the actual Opticians will thrive!:D:D

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## Uilleann

No.

They won't.

The "customers" will continue to "shop" based on price alone.  And will think they're the shizzle because they "outsmarted" the "system" and got their plastic lenses and junk frames (BOTH pair mind you) along with their "free" eye exam for $60 bucks.

Way to go Joe Q. Public!  :hammer::hammer::hammer:

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## Pete Hanlin

Barry,

You are correct regarding assessment of pantoscopic tilt (this seems to be one of the more challenging measurements for customizing lenses to fit- personally, I believe this measurement will have to be automated if we are to acheive an acceptable level of accuracy).

Regarding vertex, I can't help but think most of the posters on this thread are missing Darryl's point.  If you are compensating for POWER, then yes- a couple mm one way or the other are of no consequence.  However, you can adapt the DESIGN to vertex distance (as well as panto and face wrap).  

Regarding the impact of customization to lens position, while I don't believe customization (of any kind) is going to make a bad design function well, I do believe the performance of a good design can be improved somewhat through customization to lens position.

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## OCP

> I agree with you this is a proper way to measure panto, but my concern is limited number of opticians that know how to do this. Some will just not get it, remember supplying lenses we are dealing with a very few knowledgable opticians and also alot of people selling lenses who the day before they were an optician there business lingo was, "would you like fries with that order". In many cases as was originally stated the method suggested may produce a more satisfied patient than a poorly trained and educated craftsman with an excellent tool. 
> 
> I will even go so far as to say Barry you could probably take a known frame fitted to an unseen patient, (Thats right one you have never even met or seen a picture of), and supply a better estimated panto than a poorly trained dispenser with a fancy panto tool.
> 
> I have expressed my concerns before and suggested the best approach maybe to only offer such customized fitting by approved and trained opticians. (This idea will fair when discussed with the Sr. VP of sales)


This is exactly what I meen. If the panto is measured perfect by all opticians everytime, it would be great, but if it´s VERY wrong it can be the reason the client cant see prober with the lenses, and then WE (the suppliers) got the problem. The same with the Vertex. If both values is measured perfect, like mono PD, FH and refracted power should be, then we would all deliver "first time" solutions every time. BUT in real life it´s another history, and with exactly Panto and Vertex we see more THEORETICAL improvements than we actually see optical noticeable improvements. The risk of doing something wrong is larger than taking the correct measures, AND therefore it could be better to make these two measures a little bit more standard in your clinics.

Vertex and Panto is NOT fixed values. So many exceptions. How do you measure the fitted Vertex? With a frame with plano lens? And how do you mount a +5D in a frame? With the groove to the front or in the middle, and does this influence the Vertex? It´s actually ridicullous to say 13½ mm vertex is better than 12 or 15.! The glasses in +5 is changing position on the nose all day as well.
Panto is NOT a fixed measure. It´s an measure that taking into account your head position when you looking forward, and in that perspective, the eyesight angle. It will never change of cause, but the lens design will be made from the Panto Tilt you measue in your clinic, and the client must put up with a bad design (if you measure wrong) for the next 2-3 years.

Front curve is the only fixed measure that dont change value, however you stay or lay down, jumping or swimming.

For Darrryl (I always read your post and highly respect these, even though they are very technical). I actually dont see much difference in your plot 1 and 3 with 7 mm difference in Vertex. Plot 3 looks actually like a plot from an inaccurate freeform lens, and could just as well be that. Three same FF lenses will all have slightly different plots because of inaccuracy from the FF generator. Lucky for us it don´t give problems in real life, because our eyes, or more our brains, are fantastic to compensate for these small errors. Thats the same reason I think these small theoretical improvements you can make by calculation the vertex and the Panto angle is more or less useless.

For Mr. Finney. Please read all the post before you call my statements ridiculous. I have just like Darryl been analyzed progressive lenses for more than 15 years, but more in a practical view than in a technical view. I can´t take your post serious.

I still hope that this dialog can open up some of the complications we have with this new technology. No doubt that all new FF individual lenses (included the Auto II) works a lot better than conventional lenses, but it would be better, in my opinion, if Shamir, Zeiss, Rodenstock and Essilor, would handle these two measure different, to make it more easy and safe to sell these products. I would guarantee it would change the succes rate to "first time succes" every time.

Still the annoying Mike

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## OCP

> Barry,
> 
> You are correct regarding assessment of pantoscopic tilt (this seems to be one of the more challenging measurements for customizing lenses to fit- personally, I believe this measurement will have to be automated if we are to acheive an acceptable level of accuracy).


Exactly. :cheers:

Finally we are reaching some understanding.

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## Darryl Meister

> I actually dont see much difference in your plot 1 and 3 with 7 mm difference in Vertex.


The third plot has nearly 1.00 D more unwanted peripheral astigmatism compared to the first plot as well as 0.50 D of unwanted astigmatism over the entire near zone.




> Plot 3 looks actually like a plot from an inaccurate freeform lens, and could just as well be that. Three same FF lenses will all have slightly different plots because of inaccuracy from the FF generator. Lucky for us it don´t give problems in real life, because our eyes, or more our brains, are fantastic to compensate for these small errors.


I agree that a free-form surfacing process with poor process engineering and inadequate quality control can deliver poorer quality lenses compared to traditional semi-finished lenses. However, if you are seeing 1.00 D of unwanted astigmatism in your free-form lenses, that is pretty significant, even for "bad" free-form surfacing.

Yes, the human eye can tolerate small errors. Still, even small errors can degrade visual acuity and contrast sensitivity. For that matter, many individuals may or may not notice a significant difference in picture quality between DVD and Blu-Ray, but there are certainly a lot of consumers out there who want the best picture quality available.

In any event, I guess as long as you aren't charging more for free-form lenses that offer no additional forms of optical customization, however small the benefits of that customization to the wearer may be in your opinion, it really doesn't matter. However, most free-form lenses are positioned at "premium" price points, so what are these lenses offering to the wearer to command this higher price tag?

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## Uilleann

> ...For that matter, many individuals may or may not notice a significant difference in picture quality between DVD and Blu-Ray...



Wow.  Seriously?  They clearly need a current eye exam then, and some new specs.  Send them MY way!  ;)  How can you NOT see the difference between the two?!?!  It's rather huge-ish.  :p:D

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## Fezz

> Wow. Seriously? They clearly need a current eye exam then, and some new specs. Send them MY way! ;) How can you NOT see the difference between the two?!?! It's rather huge-ish. :p:D


 
He forgot to say:

"When viewed through polycarbonate lens material,............."


 :Eek: :cheers::cheers::cheers:;)

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## Uilleann

Oh Snap!  :p:p:p:cheers::cheers::cheers:

P.S.  Did you see my self-autographed PD stick?  You promised me - and then fell through, so I had to....er....improvise!  

http://www.optiboard.com/forums/show...402#post323402

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## YrahG

This thread brings up some very interesting points.

Opticians are not well equipped or knowledgble enough at this point to handle certain measurements required to fit these new individualized designs.Some labs would rather keep breakages low using older techniques than educate their customers on how to utilize the newest technology.Some labs have poor QC standards and little understanding of what they are making.Again I must reiterate I find the most important aspect to provideing a quality FF design encompasses all areas of our trade, the design must be solid, the lab making the design must understand at least the basics of what they are providing, the opticians needs to supply said lab with fairly accurate data, the said lab needs to have stringent Q standards in pace.

I for one would be thoroughly ****** if my lab decided they were going to take away my ability to provide accuracy by giving me a 5, 9, 12 tilt measure instead of allowing me to accurately provide what the software vendor built in.  I would drop this lab like a bad habit.  Don't get me wrong I understand the reasoning behind such a procedure, but I am not the average optician and will not tolerate a lab enforcing me to be that.  This may sound harsh, but let the labs stay in their place.  I provide the data you create based on MY DATA.

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## OCP

> This thread brings up some very interesting points.
> 
> Opticians are not well equipped or knowledgble enough at this point to handle certain measurements required to fit these new individualized designs.Some labs would rather keep breakages low using older techniques than educate their customers on how to utilize the newest technology.Some labs have poor QC standards and little understanding of what they are making.Again I must reiterate I find the most important aspect to provideing a quality FF design encompasses all areas of our trade, the design must be solid, the lab making the design must understand at least the basics of what they are providing, the opticians needs to supply said lab with fairly accurate data, the said lab needs to have stringent Q standards in pace.
> 
> I for one would be thoroughly ****** if my lab decided they were going to take away my ability to provide accuracy by giving me a 5, 9, 12 tilt measure instead of allowing me to accurately provide what the software vendor built in. I would drop this lab like a bad habit. Don't get me wrong I understand the reasoning behind such a procedure, but I am not the average optician and will not tolerate a lab enforcing me to be that. This may sound harsh, but let the labs stay in their place. I provide the data you create based on MY DATA.


 
Many would prefer the same as you. No doubt. The three different tilt, call it A, B & C was only a solution to awoid wrong orders. Lets say you visuel could see that the tilt was very oblique, so you order C (12 degrees) but you was actually measuring 15 or 10 degrees. This 3 degrees difference will not spoile the lens design at all.! But if you by mistake was measuring 5 degrees (and that is easy) then you could have adaption issues. So by doing this value a little more standard you can avoid many non adapts or adaption issues.

Mike

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## YrahG

> Many would prefer the same as you. No doubt. The three different tilt, call it A, B & C was only a solution to awoid wrong orders. Lets say you visuel could see that the tilt was very oblique, so you order C (12 degrees) but you was actually measuring 15 or 10 degrees. This 3 degrees difference will not spoile the lens design at all.! But if you by mistake was measuring 5 degrees (and that is easy) then you could have adaption issues. So by doing this value a little more standard you can avoid many non adapts or adaption issues.
> 
> Mike


So your saying I can visually determine 5, 9, and 12 but I don't have the capacity to verify visually whether I got a measure of 5, 9, or 12.  This makes no sense, I could just as easily verify my measured results using a visual method, carpenters have a saying that would apply very well here, "measure twice cut once".  As a lab if you are seeing this as an issue you need to isolate the offices that are having consistent issues and send your reps out to educate them onn proper fitting techniques and if thisdoesn't work change your remake policy or prices to ensure that it does not effect your bottom line.  If I could use an analogy your suggest putting training wheels on a harley.

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## OCP

> So your saying I can visually determine 5, 9, and 12 but I don't have the capacity to verify visually whether I got a measure of 5, 9, or 12. This makes no sense, I could just as easily verify my measured results using a visual method, carpenters have a saying that would apply very well here, "measure twice cut once". As a lab if you are seeing this as an issue you need to isolate the offices that are having consistent issues and send your reps out to educate them onn proper fitting techniques and if thisdoesn't work change your remake policy or prices to ensure that it does not effect your bottom line. If I could use an analogy your suggest putting training wheels on a harley.


The issue is not what YOU are able to do right. I´m sure you are doing a great job. The problem is more or less that the opticians are ordering a value that they dont have tools to do good enough, and they blindly trust the result from this tool. The problem is not here in Denmark alone, but all around the world you will see this is a problem. 
You are so right about more education, but this is not so easy as it sounds.
It´s even better to make the ordering of the lenses a tad more easy, and it does not help when the manufacturer needs values like the Vertex and Panto that at the same time does not count so much anyway.

----------


## Fezz

> The problem is more or less that the opticians are ordering a value that they dont have tools to do good enough, and they blindly trust the result from this tool.


Are such tools available?
Where?

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## OCP

> Are such tools available?
> Where?


Everyone has these tools. Shamir, Zeiss etc, etc.

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## Fezz

> Everyone has these tools. Shamir, Zeiss etc, etc.


Maybe in your global location, but not in mine!

I am waiting for Shamir's tool to hit the states so I can get my hands on one! Maybe you could hook me up with two or three of them?

I have an Essilor one that was giving to me by a good friend who had to get them from his contacts in Europe!

I hate to say it, but these tools are NOT widely available, at least not in the USA.

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## YrahG

> The issue is not what YOU are able to do right. I´m sure you are doing a great job. The problem is more or less that the opticians are ordering a value that they dont have tools to do good enough, and they blindly trust the result from this tool. The problem is not here in Denmark alone, but all around the world you will see this is a problem. 
> You are so right about more education, but this is not so easy as it sounds.
> It´s even better to make the ordering of the lenses a tad more easy, and it does not help when the manufacturer needs values like the Vertex and Panto that at the same time does not count so much anyway.


It is not mandatory to supply those values, if you felt that your method of ABC lens design would work why not just implement it, send out a memo to all your accounts that in the future all orders will require A, B, or C values for tilt and then define what they mean. I don't think you'll see a huge change in the remakes honestly you might actually see an increase because you are adding a level of ambiguity to your ordering system. I would personally not use your lab and I know of many other offices that are just getting used to the whole tilt and compensation thing to try and throw a A, B, C into the mix.

Or if new technology is that much of a pain just throw in the towel and sell only traditionaly surfaced lenses.

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## OCP

> It is not mandatory to supply those values, if you felt that your method of ABC lens design would work why not just implement it, send out a memo to all your accounts that in the future all orders will require A, B, or C values for tilt and then define what they mean. I don't think you'll see a huge change in the remakes honestly you might actually see an increase because you are adding a level of ambiguity to your ordering system. I would personally not use your lab and I know of many other offices that are just getting used to the whole tilt and compensation thing to try and throw a A, B, C into the mix.
> 
> Or if new technology is that much of a pain just throw in the towel and sell only traditionaly surfaced lenses.


Well we are just a wholesaler and not a lab, and mostly of our customer knows our stance on this issue, so we does not have adaption issues here.
This thread is not about how we are doing it, but how the industry are tackling this. What I want with this thread is only to put focus on this, and who knows.? Ideas start often from forums like this.  :Cool:

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## Darryl Meister

> Send them MY way! ;) How can you NOT see the difference between the two?!?! It's rather huge-ish


It really depends upon several factors, in particular the screen size and viewing distance. On a large screen at a short viewing distance, the difference in resolution between NTSC (480p) and hi-def formats (720p/1080i) should be very noticeable. On a small screen at a long viewing distance, however, the difference in resolution may not be perceptible.

----------


## HarryChiling

My take, if your having a hard time with these additional parameters don't fudge them, leave them out of the equation all together and the software will use global variables instead of user supplied data. If the design is solid and the lab has good quality control standards, your patients will still see some benefits from these individualized designs. Of course if your not measureing these additional variables then the premium category of FF which offers these dynamic variables might not be cost effective, try similar designs with static variables since the cost should be lower and the benefits the same.

----------


## Mr. Finney

> For Mr. Finney. Please read all the post before you call my statements ridiculous. I have just like Darryl been analyzed progressive lenses for more than 15 years, but more in a practical view than in a technical view. I can´t take your post serious.


Mike, I did read your entire post.  In fact, I've read every post in this thread.  I'm not calling all of your statements ridiculous, just the one.  My point is that you are saying that if a measurement is off even a little, that the finished product will be unusable ("If your power is -6D and you measure 2 mm wrong, the lenses will NOT work") & ("it will only give optical improvement if you measure both values 100% correct"), and that is just simply not correct.  The product will not be as it could be, but it certainly would be useable, and more than likely would be of as good as or better optical quality as a standard non-compensated product.

Bryan

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## Uilleann

> It really depends upon several factors, in particular the screen size and viewing distance. On a large screen at a short viewing distance, the difference in resolution between NTSC (480p) and hi-def formats (720p/1080i) should be very noticeable. On a small screen at a long viewing distance, however, the difference in resolution may not be perceptible.


I dunno - perhaps you're right.  But my myopic eyeballs can spot it across a store showroom floor - 50+ feet or so.  I hope most people are viewing their TV's a bit closer than that!  :D (but not TOO close now!):p  I must say, that even in bed, watching my 24" monitor across the room, roughly 18 feet, without my peepers on, I can still tell a marked difference between blu-ray and a standard DVD.

I hope the re-release Jaws in high def with the ol red/blue specs.  That would truly be movie-vana!  hehe

Cheers Darryl!  :cheers::cheers::cheers:

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## Mr. Finney

> I dunno - perhaps you're right.  But my myopic eyeballs can spot it across a store showroom floor - 50+ feet or so.  I hope most people are viewing their TV's a bit closer than that!  :D (but not TOO close now!):p _ I must say, that even in bed, watching my 24" monitor across the room, roughly 18 feet, without my peepers on, I can still tell a marked difference between blu-ray and a standard DVD._
> 
> I hope the re-release Jaws in high def with the ol red/blue specs.  That would truly be movie-vana!  hehe
> 
> Cheers Darryl!  :cheers::cheers::cheers:


Geez, like half a diopter myopic? :bbg:  At 18 feet with no glasses, I can't tell the difference between the tv on or off!  Of course, when you can't see, you can't hear either, so don't try that old "Can't you at least hear the tv?" stuff on me:p

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## Barry Santini

> My take, if your having a hard time with these additional parameters don't fudge them, leave them out of the equation all together and the software will use global variables instead of user supplied data. If the design is solid and the lab has good quality control standards, your patients will still see some benefits from these individualized designs. Of course if your not measureing these additional variables then the premium category of FF which offers these dynamic variables might not be cost effective, try similar designs with static variables since the cost should be lower and the benefits the same.


Agreed!
:cheers:
Barry

PS And be careful of ALL FF backside progressives with adds +2.75 and over. My experience is that they are, as a group, NOT as good because of manufacturing problems as a good front-side design.

Barry

----------


## Uilleann

> Geez, like half a diopter myopic? :bbg:  At 18 feet with no glasses, I can't tell the difference between the tv on or off!  Of course, when you can't see, you can't hear either, so don't try that old "Can't you at least hear the tv?" stuff on me:p


hehe  I'm only minus that half in one eye (the other is a bit worse!)  I didn't know that the eyes affected hearing like that...but it explains a LOT!  And here I thought it might have been the business end of all those Lear 35's when I was working out on the ramp yeas back.  :D

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## Barry Santini

> It really depends upon several factors, in particular the screen size and viewing distance. On a large screen at a short viewing distance, the difference in resolution between NTSC (480p) and hi-def formats (720p/1080i) should be very noticeable. On a small screen at a long viewing distance, however, the difference in resolution may not be perceptible.


You, Darryl, have obviously *not* viewed an NTSC picture on a 480p 32" CRT Bang & Olufsen AVANT TV.

That TV's picture, now residing in my basement den, is STILL THE MOST LIFELIKE PICTURE I HAVE EVER SEEN ON ANY TV.

I view that TV from 11 feet away.
I view my LR 50" HD Plasma from 9 feet away (also a B&O).

The AVANT, on STD definition (which is all it can display) is still superior and sharper than the plasma.

Qualitative differences do count.  Everyone whose ever seen the Avant agrees.

Same applies to FF lens designs, like Zeiss ( A truly EXCELLENT FF), IMHO.

Barry

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## Mr. Finney

> You, Darryl, have obviously *not* viewed an NTSC picture on a 480p 32" CRT Bang & Olufsen AVANT TV.
> 
> That TV's picture, now residing in my basement den, is STILL THE MOST LIFELIKE PICTURE I HAVE EVER SEEN ON ANY TV.
> 
> I view that TV from 11 feet away.
> I view my LR 50" HD Plasma from 9 feet away (also a B&O).
> 
> The AVANT, on STD definition (which is all it can display) is still superior and sharper than the plasma.
> 
> ...


Proof that Opticians in licensed states make more $$ than those in non-licensed ones:bbg:

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## Uilleann

Sweet Barry!  I got the popcorn, cold pizza and beer covered.  Jaws at your place right?!  We can wax poetic about Televue eyepieces during the boring parts.  ;)

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## Barry Santini

> Proof that Opticians in licensed states make more $$ than those in non-licensed ones:bbg:


This is true. And further, Optician owners/partners make more as well.

But we work harder too!

There's just me and my partner Bob. We do ALL the:

Dispensing
Sales
Repairs(including hidden hinges and soldering)
Orders
Fabrication (including drilling and wraps)
Queries
Bookeeeping and bill paying
Payroll
Displays attention.

There are no other helpers. Business gross last year was $895K.
(this year will be less)
We earned it every day!
And we learn so much each day from Optiboard!

Thanks for a great "pub" to meet in, Steve!

Barry

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## Barry Santini

> Sweet Barry! I got the popcorn, cold pizza and beer covered. Jaws at your place right?! We can wax poetic about Televue eyepieces during the boring parts. ;)


Do you know Tele Vue?

Barry

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## Mr. Finney

> This is true. And further, Optician owners/partners make more as well.
> 
> But we work harder too!
> 
> There's just me and my partner Bob. We do ALL the:
> 
> Dispensing
> Sales
> Repairs(including hidden hinges and soldering)
> ...


Wow Barry, that's awesome!  We do about that in our office with 7 employees!  Now mind you, all of my attempts at creating more efficiency are met with an old-school, "that's not the way we've always done it" mentality, but I would think we could do more with less, as you and your partner prove.

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## Barry Santini

> Wow Barry, that's awesome! We do about that in our office with 7 employees! Now mind you, all of my attempts at creating more efficiency are met with an old-school, "that's not the way we've always done it" mentality, but I would think we could do more with less, as you and your partner prove.


Oh, I forgot one more person..
.
Our right hand gal friday/receptionist/master-get-out-of-here"er", Mo!

B

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## Uilleann

> Do you know Tele Vue?
> 
> Barry


Are you _kidding_ me Man???  Hansen Planetarium - 10 years.  (+ 3 as a docent volunteer), and Telescope/eyepiece retail for another three after that.  If I could afford them - I'd practically_ breathe_ Tele Vue!  I love them almost as much as my poly lenses and Essilor!  :D:D:D _(blowing a kiss in Fezz's general direction!)_

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## Mr.Goggle

Fascinating Mike, thanks for posting!

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## Pete Hanlin

He forgot to say:

"When viewed through polycarbonate lens material,............."

While the above statement is funny (brought a smile even to my lips), it is unfortunately another example of disinformation.  _Fact_ is, in independent clinical evaluations, subjects prefer polycarbonate over Trivex (which is supposed to provide "superior clarity").  Not by statistically significant margins, but the point being polycarbonate provides vision that is every bit as good- if not better- than most other ophthalmic materials.  Not picking on Trivex (even though I personally can't for the life of me understand why this material exists, professionally speaking I am employed by a manufacturer of this material).

Unfortunately, there is a _ton_ of disinformation that has been scattered throughout our industry regarding material properties, design characteristics, etc.  These snippets are treated as "fact" and repeated by people in the field who have neither the experience nor education to "know better" (I'm not including anyone on this post in that group- but the fact is, most opticians in the US are not formally educated or apprenticed).

I think this is the point behind the initial response to this thread.  Making blanket (and untrue) statements that customization to position of wear is inconsequential- or that polycarbonate is somehow an inferior ophthalmic material- spread disinformation in an environment where speculation is often mistaken as fact.

To clarify- position of wear for an ophthalmic lens (particularly a progressive) does play a measurable role in visual perception.  

Polycarbonate is like any other ophthalmic material: when processed and fit correctly, it provides excellent vision.  Incorrect processing and/or fitting reduces its performance.

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## HarryChiling

> He forgot to say:
> 
> "When viewed through polycarbonate lens material,............."
> 
> While the above statement is funny (brought a smile even to my lips), it is unfortunately another example of disinformation. _Fact_ is, in independent clinical evaluations, subjects prefer polycarbonate over Trivex (which is supposed to provide "superior clarity"). Not by statistically significant margins, but the point being polycarbonate provides vision that is every bit as good- if not better- than most other ophthalmic materials. Not picking on Trivex (even though I personally can't for the life of me understand why this material exists, professionally speaking I am employed by a manufacturer of this material).
> 
> Unfortunately, there is a _ton_ of disinformation that has been scattered throughout our industry regarding material properties, design characteristics, etc. These snippets are treated as "fact" and repeated by people in the field who have neither the experience nor education to "know better" (I'm not including anyone on this post in that group- but the fact is, most opticians in the US are not formally educated or apprenticed).
> 
> I think this is the point behind the initial response to this thread. Making blanket (and untrue) statements that customization to position of wear is inconsequential- or that polycarbonate is somehow an inferior ophthalmic material- spread disinformation in an environment where speculation is often mistaken as fact.
> ...


PAL designs require that a patient view off axis to read and the fitting cross is anywhere from 2 to 6mm above this point with the majority at 4mm, the optical center being surfaced at the PRP or in the case of prism thinning lower than the PRP, if the average min seg hgt is 18mm minus the 4mm seg to PRP we have a length of 14mm off axis to plug into our Ch Abb equation. In the distance with no prism thinning we would have a 4mm off axis point, not significant IMO. This off axis viewing could create issues and in most cases I believe people attribute it to the design rather than the material but this is just me speculating. I think prism thinning would allow for less of a problem in the reading while increaseing the effect on distance. With shorter corridor progressives if the problem did truly exist the way I imagine it, it will be less of an issue. 

Ch Abb alone is not significant enough of an issue, but most of the literature available on most abberations will lead the average joe to believe that each is a seperate entity and has no effect on the other, a more educated optician would realize that the compound effects of poor material properties, ANSI, and other design flaws can add up to significant errors. Nothing wrong with poly especially now that FF exists less aberration from design or manufactureing flaws means that the material has less to make up for.

To add a note, the foundation of good lens design starts with the material, in every text I have read the material selection is a part of lens design so to play down poly's attributes isn't the way Ido things, that being said I used to dispense more poly than any other maetrial in all the offices I worked because in the majority of cases when teh pros and cons were weighed out it made sense, but when the patient performance suffered I took that into consideration and used other materials.  I still think there is a place for spectralite, evoclear, and the other mid index lenses.  I like the variety in choice it keeps up sharp, now if I had a preference I would replace poly with 1.60 not trivex.  Honestly I still thin trivex is more a novelty.

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## Barry Santini

> PAL designs require that a patient view off axis to read and the fitting cross is anywhere from 2 to 6mm above this point with the majority at 4mm, the optical center being surfaced at the PRP or in the case of prism thinning lower than the PRP, if the average min seg hgt is 18mm minus the 4mm seg to PRP we have a length of 14mm off axis to plug into our Ch Abb equation. In the distance with no prism thinning we would have a 4mm off axis point, not significant IMO. This off axis viewing could create issues and in most cases I believe people attribute it to the design rather than the material but this is just me speculating. I think prism thinning would allow for less of a problem in the reading while increaseing the effect on distance. With shorter corridor progressives if the problem did truly exist the way I imagine it, it will be less of an issue. 
> 
> Ch Abb alone is not significant enough of an issue, but most of the literature available on most abberations will lead the average joe to believe that each is a seperate entity and has no effect on the other, a more educated optician would realize that the compound effects of poor material properties, ANSI, and other design flaws can add up to significant errors. Nothing wrong with poly especially now that FF exists less aberration from design or manufactureing flaws means that the material has less to make up for.
> 
> To add a note, the foundation of good lens design starts with the material, in every text I have read the material selection is a part of lens design so to play down poly's attributes isn't the way Ido things, that being said I used to dispense more poly than any other maetrial in all the offices I worked because in the majority of cases when teh pros and cons were weighed out it made sense, but when the patient performance suffered I took that into consideration and used other materials. I still think there is a place for spectralite, evoclear, and the other mid index lenses. I like the variety in choice it keeps up sharp, now if I had a preference I would replace poly with 1.60 not trivex. Honestly I still thin trivex is more a novelty.


Gee Harry, sounds like stuff in my ABOM paper...

B

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## HarryChiling

> Gee Harry, sounds like stuff in my ABOM paper...
> 
> B


Yes Barry you have been assimilated. :bbg: I have Darryl's paper too and a few others. I like reading and I like smart folks.  You know when Darryl and Pete reply in a thread it's gotta be a good one.  Your not to shabby either. ;)

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## OCP

[QUOTE=Darryl Meister;323372]


According to your post, your company's Autograph II lens is not fully customized for the position of wear anyway, which would exclude it from the class of lenses including ZEISS Individual and Rodenstock Impression ILT.
QUOTE]

Darryl.
Happy holliday to all here on this board.
I´m realy curious about this point of view.

So what you actually write is, the more measures you got, the better optical solutions you get?

Did you know that shamir philosophy is a bit different?
-and that sometimes "simple is better".
Maybe thats why someone cant use Individual and prefer Gradal Top?

You can actually destroy a great optical lens design with all these data that can go wrong for simple reasons: The frame is not FIXED, and the client change lifestyle. 

Thats the main reason that Panto and Vertex is uninteresting measures.
The same with lifestyle examination etc.

*It´s all about handling of abberations, so the lenses will never be better than the software programmer in the end. Thats another fact.!*

I don´t say that Impression and Individual not are great lenses, they certain are, but I think someone, in the name of evolution, are forgetting what it´s all about.

Thats the reason I think Autograph II is a step ahead other manufacturer because they have already admitted this a long time ago. It´s not a question about who make the lens most individual, but simply who got the best programmer? (We all know Israel got some of the best programmer out there). :cheers:

Mike

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## Barry Santini

I think the failure of any POW measured and compensated PAL correction is less about the accuracy and/or validity of the obtained (or assumed) POW values, and more about the following things (in order of importance):

1. The Rx you begin with.
2. The assumptions made in *any* given POW compensated algorithym.
3. The limits of FF manufacturing, particularly in highers adds (over +2.50)

FWIW

Barry

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## AWTECH

> I think the failure of any POW measured and compensated PAL correction is less about the accuracy and/or validity of the obtained (or assumed) POW values, and more about the following things (in order of importance):
> 
> 1. The Rx you begin with.
> 2. The assumptions made in *any* given POW compensated algorithym.
> 3. The limits of FF manufacturing, particularly in highers adds (over +2.50)
> 
> FWIW
> 
> Barry


What problems with over +2.50 ADDs do you have?

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## Barry Santini

in the cases where the client was wearing comfort or Physio, we're  seeing decreased utility, and comments such as a narrower intermediate and reading zone.  When we return them to their original lens style, in the new Rx, they immediately check the intermediate and reading and pronounce it "OK"

FWIW

Barry

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## YrahG

> in the cases where the client was wearing comfort or Physio, we're seeing decreased utility, and comments such as a narrower intermediate and reading zone. When we return them to their original lens style, in the new Rx, they immediately check the intermediate and reading and pronounce it "OK"
> 
> FWIW
> 
> Barry


I believe this is a more a generation of FF design rather than a FF processing itself.  For the most part the current FF designs have been optimizing the distance zone, where the molded lenses have come to a point where each manufacturer offers their best interpretation of a compromise between distance, intermediate and near.  I believe that designs are starting their evolution all over again with FF, maybe not from the start, but definately not from where they left off in some cases.

It will get better.

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## Barry Santini

> I believe this is a more a generation of FF design rather than a FF processing itself. For the most part the current FF designs have been optimizing the distance zone, where the molded lenses have come to a point where each manufacturer offers their best interpretation of a compromise between distance, intermediate and near. I believe that designs are starting their evolution all over again with FF, maybe not from the start, but definately not from where they left off in some cases.
> 
> It will get better.


Interesting point.  I'm gonna keep my eyes and mind open to what may be comin' down the pike.

Thanks

barry

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## Darryl Meister

> Darryl. Happy holliday to all here on this board.


Hi Mike. Happy holidays to you, too.




> So what you actually write is, the more measures you got, the better optical solutions you get?


Yes. The use of more dimensions of measurement generally improves the accuracy of the outcome, regardless of the context.

But here is another vision care analogy that may resonate a little more: Just as a high-order vision correction can offer crisper vision than a sphero-cylindrical correction; and a spherocylindrical correction can offer crisper vision than a spherical correction; and a spherical correction can offer crisper vision than no correction at all.




> You can actually destroy a great optical lens design with all these data that can go wrong for simple reasons: The frame is not FIXED


I think I actually addressed this point in several earlier posts in this thread and others, but a bit of consideration would reveal how invalid this argument is:

1. Lens designs optically customized for the position of wear do not suddenly stop working when the lens is moved slightly out of position. On the contrary, since the lens design was calculated for the patient's actual position of wear, changes due to any small movments should have less impact on optical performance because you started off closer to the true "target" values in the first place.

2. Many semi-finished lenses are optically optimized for a specific position of wear. I believe Shamir refers to their version of this technique as "eye point technology." Consequently, using your rationale, many premium semi-finished progressive lens designs should suffer from the very same deteriorations in optical performance whenever the lenses shift slightly.

Lenses do not "fail" to work when the position of wear changes. The optical differences introduced by changes to the position of wear will vary as a function of lens power and lens tilt or movement.




> and that sometimes "simple is better".


I don't disagree that simple is better. But that's not what we're really discussing here.

Your (Shamir's) solution doesn't require any less work on the part of the eye care professional, since position of wear measurements can still be supplied with Autograph II. Further, neither Shamir Autograph II nor Zeiss Individual requires these measurements, if the eye care professional chooses not to provide them.

But what Zeiss Individual does with those measurements once they have been provided seems to differ significantly from the approach used for Shamir Autograph II. Well beyond basic prescripiton optimization, the actual lens design is manipulated on a point-by-point basis during the optical design process using these position of wear parameters.




> It´s all about handling of abberations, so the lenses will never be better than the software programmer in the end. Thats another fact.!


I didn't really understand your point here.




> Thats the reason I think Autograph II is a step ahead other manufacturer because they have already admitted this a long time ago.


I may have misunderstood you again; they're a step ahead because they are doing less?




> It´s not a question about who make the lens most individual, but simply who got the best programmer? (We all know Israel got some of the best programmer out there


Actually, programming isn't the difficult part at all, which is why many industries in the US now out-source programming projects to cheaper labor in other countries. There is nothing special about the code.

Figuring out what to program, on the other hand, is the real challenge. Optical design and advanced mathematics are the essential elements of free-form calculation software that does more than just add Progressive Surface A to Prescription Surface B.

I understand that you are a Shamir distributor, but you seem to be trying to convince people that if Shamir doesn't do something, or can't do something, we must be better off without it. This may be hard for a lot of people to swallow.

In any case, Shamir must see some sort of value in position of wear measurements, since they recently developed a tool to measure these and you can submit the values when ordering several of their products...

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## OCP

> Hi Mike. Happy holidays to you, too.
> 
> 
> Yes. The use of more dimensions of measurement generally improves the accuracy of the outcome, regardless of the context.
> 
> But here is another vision care analogy that may resonate a little more: Just as a high-order vision correction can offer crisper vision than a sphero-cylindrical correction; and a spherocylindrical correction can offer crisper vision than a spherical correction; and a spherical correction can offer crisper vision than no correction at all.
> 
> 
> I think I actually addressed this point in several earlier posts in this thread and others, but a bit of consideration would reveal how invalid this argument is:
> ...


Hi Darryl.

Sorry for my lack of englinsh knowledge. 
Because of that it is sometimes a bit difficult to write perfect, for you and other to understand the meening correctly.

The Auto II do need the same measurement just as Individual and Impression does and Shamir are handling the data just as you do with the Individual.
Shamir calculate the data with a software tool called "Eye Point Technology" just as you said, and you use your specific software. There is no different about that.

I say it again. All I write is my personal opinions, and not Shamir.

I will try to explain my opinion in a pedagogic manner:
If you test Individual on 100 persons, will you then get a higher succes rate by measure Vertex and Panto on 50 persons, and use default on the rest 50.?

I´m sure you will claim YES, but realy, I think you don´t have the answer. The only answer you got is an THEORETHICAL answer. 

You are not stupid at all, and know a lot about lenses in a technical way, but what about customising lenses in real life? Have you ever dealed with the issues out there?

Again, because of my lack of english writing, I realy don´t think you understand me, or maybe you just don´t want to understand me, because you prefer to let Individual look more advanced than Auto II.?
I tell you. It´s not. It´s fine with me you don´t think. You and I will never agree on that ofcause. 

This is, somehow, your forum, so I will not publish bad informations about Individual, as you do with Auto II. I will get banned from here, and I don´t want.

I will stop discussing more in this thread. It´s pointless

Happy new year.

Mike

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## sandeepgoodbole

The Rx Power = The Planet orbiting around the Sun of the Vision. The facial Wrap= The Altitude.  The Pentascopic Tilt = The latitude. Vertex Dist = The Longitude. The Frame = The House number. Any error in any of these would cause the user feel  "NOT AT SWEET HOME."

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## YrahG

Eye Point Software = Creates the design, incorporateing may of the variabels discussed here and more. http://www.shamirlens.com/ecp/ecp.aspx
Prescriptor Software = Controls the digital processing, incorporating frame data as well to ensure proper aesthetics. http://www.shamirlens.com/ecp/freeform.aspx


Either Zeiss Individual or Shamir Autograph II will provide a greater degree of accuracy to a patients personal needs.  Their are protocals in place for a simple optician and a more advanced optician to use these designs.  Without the additional data the lens can still be optimized to a degree using global variables for the missing data and optimizing the base curve and resulting aberrations to the prescription.  With the supplie data the same optimizations occur, but now the design is optimized as well to match the patients prescripton as well as fitted data.  The simpler is better philosophy isn't necessarily a break through that Shamir thought of since it provides a more accurate or just as close product, it is more to deal with the varying levels of optician/fitter skills.  This roadblock is so consistent that this thread is now pages long with some still not understanding some of the basic concepts of how this new breed of lens works.

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## Darryl Meister

> If you test Individual on 100 persons, will you then get a higher succes rate by measure Vertex and Panto on 50 persons, and use default on the rest 50.? I´m sure you will claim YES, but realy, I think you don´t have the answer.


Yes, we have actual wearer data and clinical studies to support this claim for Zeiss Individual, including a large scale study conducted in Europe. In fact, we expect to have more positive results to share quite soon. That said, I have yet to see any clinical evidence that _disproves_ the benefits of customization for the position of wear.




> You are not stupid at all, and know a lot about lenses in a technical way, but what about customising lenses in real life? Have you ever dealed with the issues out there?


I'm not sure what you mean by "dealing with the issues out there." Nevertheless, since I provide technical support and training to our customers and to our sales force, yes, I must constantly deal with these issues in the field.




> You ... know a lot about lenses in a technical way... The only answer you got is an THEORETHICAL answer


In my job, anything I say regarding product performance must be capable of withstanding a high degree of scrutiny in order for our attorneys to approve it. Unlike others, who may get away with "smoke and mirrors" marketing claims, I don't have the luxury of making wild or vague product claims based upon opinion and anecdotal evidence or that otherwise lack some scientific basis.




> This is, somehow, your forum, so I will not publish bad informations about Individual, as you do with Auto II. I will get banned from here, and I don´t want.


1. This is not my forum, and you are welcome to say what you want, at least within the posted guidelines of OptiBoard. I do not even moderate the Progressive Lens forum. And I have yet to see any of the moderators of this forum ban someone for endorsing a product.

2. Actually, I generally refrain from product-specific discussions, unless I am simply answering a question. It is only your constant insistence upon questioning the merits of a legitimate technology -- optical customization for the position of wear -- to endorse your own product that has prompted me to respond in the first place.

3. I haven't provided any information about Shamir Autograph II, "bad" or otherwise. If you review this thread carefully, only those individuals associated with Shamir, particularly yourself, have implied that the product offers more limited optical customization.

Mike, whether I agree with your points or not, I can assure you that I welcome you here at OptiBoard. And I am sure that the other members feel the same way. In fact, since Shamir has had surprisingly little representation here, I would actually encourage you to continue participating.

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## Laurie

Hi Guys (and Gals),

Hope you are having a great holiday so far, if I forget to say it later, "Happy Happy New Year!"

Mike, Darryl, I think you are both closer to opinions/schools of thought rather than far apart.

Some ECP's think that position of wear/as-worn measurements don't matter, but we are approaching a new paradigm shift here, our patients/clients will have the last word. I think there are alot of visually-sensitive patients/clients out there who can tell the difference.

While my full time job is opticianry education (Go HCC!), I also do many CE seminars for opticians on behalf of Shamir. It has been my experience that the learning curve is actually quite larger than you would expect!

Case in point: The difference between providing an OC height or a fitting height for a SV back surface FF, and understanding about Martin's tilt, ect... or, using optical common-sense in regard to frame curvature and high Rx's, ect... Or, even closing one eye at a time while taking measurements to avoid cross-parallax error while the dominant eye takes over!

I'm not in a position to claim 'spokesperson status', however, I will be happy to share what I have learned, and points that need to disseminate to the ECP's, and ultimately, the patients/clients.

The Shamir Autograph II series can be optimized for As-Worn (panto, tilt, VD)...we can debate the theoretical / Vs. / practical applications of this, however, if it looks better in theory, it is likely better in practice. If these measurements are not provided, the visual software (eyepoint technology/prescriptor) will default to global norms, still yielding a better visual product.

Fully customized back surface, personalized PALs (and SV) incorporating position of wear are the wave of the future. Super computers allow us to do SO MUCH more than before! Instead of assuming (remember how to spell ***-u-me?) that opticians/ECP's can't handle the technical skills required to understand, measure for, explain, verify this new generation of lenses, lets get together and talk about the benefits:

*Optics closer to the eye (back surface design)
*Enhanced field of view (pin-hole effect)
*Better aberration/power control with additional as-worn measurements
*Real-time design...no more molds, where a range of Rx's are incorporated, if you are not in the middle of the mold bell-curve, your visual experience will not be as good as it will be with complete personalization
*Many more material options, starting with semi-finished blanks.

In addition to teaching/presenting seminars, I fill in/dispense for a friend w/a high-end optical boutique in Tampa...we fit ALOT of Auto II's... our patients/clients comment on the 'wow-factor' all the time.

And, in addition to eyepoint technology and the prescriptor calculations, the ECP can send the frame to the lab for tracing for further optical enhancements, 'free-frame technology', which considers the position of wear, and the placement of the pupils, near PD, along the convergence line to dynamically place the near-zone to full capacity, not simply calculating it on the frame 'B' dimension

Whats not to love about all of these options?

We have ALOT of work ahead of us educating ECP's and patients on these new technologies and opportunities.


: )

Laurie

----------


## YrahG

> Hi Guys (and Gals),
> 
> Hope you are having a great holiday so far, if I forget to say it later, "Happy Happy New Year!"
> 
> Mike, Darryl, I think you are both closer to opinions/schools of thought rather than far apart.
> 
> Some ECP's think that position of wear/as-worn measurements don't matter, but we are approaching a new paradigm shift here, our patients/clients will have the last word. I think there are alot of visually-sensitive patients/clients out there who can tell the difference.
> 
> While my full time job is opticianry education (Go HCC!), I also do many CE seminars for opticians on behalf of Shamir. It has been my experience that the learning curve is actually quite larger than you would expect!
> ...


Thank you that was a great post and it's nice to see someone with knowledge about the Shamir products here.  Most of the information I have is from patents and research.

----------


## Darryl Meister

Hi Laurie. Hope all is well with you and your family down in Florida.




> Shamir Autograph II series can be optimized for As-Worn (panto, tilt, VD)... Real-time design...


If you are stating that they re-design each lens based upon the prescription and position of wear measurements, as opposed to simply compensating the prescription for lens tilt, this is actually a pretty significant claim. And certainly at odds with some of Mike's statements. Have any of the technical guys at Shamir ever actually confirmed this for you?

----------


## OCP

> Hi Laurie. Hope all is well with you and your family down in Florida.
> 
> 
> 
> If you are stating that they re-design each lens based upon the prescription and position of wear measurements, as opposed to simply compensating the prescription for lens tilt, this is actually a pretty significant claim. And certainly at odds with some of Mike's statements. Have any of the technical guys at Shamir ever actually confirmed this for you?


There is no difference in what Laurie said and what I said. What you dont want to understand is simply that, in my oppinion, you do have two measures, Panto & Vertex, that actually does´t give the optical improvement you say it will.
As long you dont have the refracted AND the fited Vertex and the power is below 5D you will have only get theoretichal improvements. Not in real time. 
-and no one can measure these two values correct anyway.

If what you claim are correct, Individual must be the best lens in the market, and should be the lens that would solve all progressive adaption issues.!!!

If you realy got balls, you should ask Optiboard to make a poll: Have you ever had adaption issues when fitted Individual.?

You know just as anyone else here on this board, that Individual is NOT the answer of perfect vision and perfect adaption every time.! Well actually I will think you got more WOW from Auto II than from Individual. Lets make a poll of this as well.


Laurie, thanks for your great post, and you are all right, because it´s all about education. -not to forget education of which parameters that are important and which are not.

Mike

----------


## Darryl Meister

> There is no difference in what Laurie said and what I said.


I wasn't left with that impression after reading your posts.




> If what you claim are correct, Individual must be the best lens in the market, and should be the lens that would solve all progressive adaption issues.!!!


I've never made any claims to that effect. Remember that we were discussing the merits of customization for the position of wear, not whether Zeiss Individual is the best progressive lens out there. I think that goes without saying. ;)

Progressive lens adaptation problems are often due to a number of factors, many of which are unavoidable in progressive lens design. Fully customized lenses like Zeiss Individual maximize vision quality by freeing lens designers from the constraints of mass lens production using a handful of lens blanks. Customized lenses do not and cannot free lens designers from the mathematical constraints of progressive surfaces, which necessitate some degree of unwanted astigmatism and distortion over the lens surface.

As for whether Individual is the best lens on the market, I can only report what I have observed: it just won the OLA's Award of Excellence in Lens Design, it has achieved some of the lowest non-adapt rates among all of our progressive lenses, it has done extremely well in clinical studies, and the designs generally look great against leading competitors.

I have no doubt that some of Individual's success is due to its extensive optical customization (and not just power compensation). But I have also observed a great deal of success among several competitive free-form lenses as well. I'm sure that there are several products on the market that offer patients an improved visual experience.




> You know just as anyone else here on this board, that Individual is NOT the answer of perfect vision and perfect adaption every time


Again, this conversation should focus on optics, not any one manufacturer's specific product. I was defending an optical principle, not a brand name. And I would prefer not to use this forum as a vehicle to promote my company's products; I save that stuff for the marketing pieces. Besides, I already have a big ZEISS shield next to my name to clarify my affiliation.




> As long you dont have the refracted AND the fited Vertex and the power is below 5D you will have only get theoretichal improvements


I've already explained the difference between _power compensation_ and _design optimization_, and provided graphical comparisons for you to review, so I will simply refer back to my earlier posts (in particular, see 13).




> Have you ever had adaption issues when fitted Individual.?


As a matter of fact, I don't really need to conduct a poll. I get a monthly report from our lab network that details how many Individual lenses were returned as "non-adapts." For laboratories in the US, this number was at 0.8% as of last month according to the data from our laboratory management system.




> it´s all about education.


I agree completely. But I wonder whether eye care professionals are truly being exposed to quality, unbiased education or just marketing propaganda...? Food for thought.

----------


## Fezz

> But I wonder whether eye care professionals are truly being exposed to quality, unbiased education or just marketing propaganda...? Food for thought.



Many of us have been wondering the same thing for a very long time! I feel that until I see some real unbiased education, I'll continue to assume that everything is marketing propaganda that I must wade through and draw my own conclusions!


:cheers::cheers::cheers:

----------


## OCP

> I wasn't left with that impression after reading your posts.


I´m sorry for that misunderstanding. A lack of my english writing I guess.


[/QUOTE] As for whether Individual is the best lens on the market, I can only report what I have observed: it just won the OLA's Award of Excellence in Lens Design, it has achieved some of the lowest non-adapt rates among all of our progressive lenses, it has done extremely well in clinical studies, and the designs generally look great against leading competitors. [/QUOTE]
Congratulations with that :cheers:

[/QUOTE] I have no doubt that some of Individual's success is due to its extensive optical customization (and not just power compensation). But I have also observed a great deal of success among several competitive free-form lenses as well. I'm sure that there are several products on the market that offer patients an improved visual experience. [/QUOTE]

Nice to know. I wasn't left with that impression after reading your posts. (to use your own text)


[/QUOTE] Again, this conversation should focus on optics, not any one manufacturer's specific product. I was defending an optical principle, not a brand name. And I would prefer not to use this forum as a vehicle to promote my company's products [/QUOTE]

I agree 


[/QUOTE] I've already explained the difference between _power compensation_ and _design optimization_, and provided graphical comparisons for you to review, so I will simply refer back to my earlier posts (in particular, see 13). [/QUOTE]

You tell me that when changing the vertex 5-6 mm you get 1D difference in _design compensation??_ Have you ever wondered if this could be the reason someone gets adaption issues when changing to Individual? I must tell you, that I raise doubts about that claim (-and that´s my problem I know).


[/QUOTE] As a matter of fact, I don't really need to conduct a poll. I get a monthly report from our lab network that details how many Individual lenses were returned as "non-adapts." For laboratories in the US, this number was at 0.8% as of last month according to the data from our laboratory management system. [/QUOTE]

Shamir can flaunt of this claim rate as well, and was not the question. It was about adaption ISSUES. Not that the client could not get used to the lenses.
A poll is not usefull I agree, but funny to hear what a few anonyme members here are thinking. 

Happy new year

Mike

----------


## OCP

> Many of us have been wondering the same thing for a very long time! I feel that until I see some real unbiased education, I'll continue to assume that everything is marketing propaganda that I must wade through and draw my own conclusions!
> 
> 
> :cheers::cheers::cheers:


I fully agree.
Many companies are selling/learning you a HISTORY about their lenses.
Eye mover, lifestyle, previus lenses, etc, etc.
It´s more easy to sell a history than explain the philosophy behind the lenses, and it´s more easy to convince the opticians why this new lens is better than the other.

So look at the informations as marketing propaganda and make your own conclusions. Not stupid at all.

Mike

----------


## Darryl Meister

> Nice to know. I wasn't left with that impression after reading your posts


If you in fact interpreted one of my posts to suggest, either directly or indirectly, that "_Individual must be the best lens in the market, and should be the lens that would solve all progressive adaption issues.!!!_" please identify the post in question, and I will correct it immediately.




> Shamir can flaunt of this claim rate as well, and was not the question. It was about adaption ISSUES. Not that the client could not get used to the lenses.


I guess I don't understand what you are asking then, if you do not consider the rate of progressive non-adapts to be an indication of "non-adapt issues." Or what any of this has to do with the position of wear.

In any case, I don't expect anyone to wear any progressive lens without _some form_ of "adaptation issue," at least with a non-negligible addition power, since the optical compromises inherent in the design of progressive lenses result in certain visual disturbances that are unavoidable. We can simply attempt to minimize these disturbances through thoughtful lens design.




> You tell me that when changing the vertex 5-6 mm you get 1D difference in _design compensation??_ Have you ever wondered if this could be the reason someone gets adaption issues when changing to Individual?).


I didn't really understand this question at all or where your numbers are coming from. And you seem to have fused two separate terms, prescription compensation and design optimization, into one ambiguous term...?

You _seem to be_ suggesting that changes to the lens design as a result of compensating or optimizing for the position of wear can cause more non-adapts. Of course, this is in direct contradiction to your earlier claim that the position of wear has little if any visual significance in most cases. After all, if the changes in power due to changes in the position of wear are not significant enough to affect vision, how can the corresponding adjustments to the lens powers (which are of similar magnitudes) either improve or worsen vision?




> It´s more easy to sell a history than explain the philosophy behind the lenses,


After 4 pages of posts, I must say that I agree completely.

----------


## obxeyeguy

> If you are stating that they re-design each lens based upon the prescription and position of wear measurements, as opposed to simply compensating the prescription for lens tilt, this is actually a pretty significant claim. And certainly at odds with some of Mike's statements. Have any of the technical guys at Shamir ever actually confirmed this for you?


I for one would still like to see an answer to this question.

----------


## Barry Santini

(acting as corner boxing coach/trainer here..)

Let's not forget some not too trivial points that need to be restated regarding traditional, non-ff, non POW comp'd progressives:

none

NONE

*NONE*

*NONE*

Of the best traditional progressives were ever designed or imagined to be used with zero panto tilt or zero face form.  Reducing the obliquity of incidence for the lateral peripheral zones, as well as addressing the reading corridor, required deisgners to recommend 8-10 degrees of panto tilt and 5 to 7 degress of face form.  In most cases, the vertex assumed was 13 to 14mm.

So, even traditiional progressives has "assumed/default" values for the intended design's position of wear.  In this way, I agree with Mike the these values, hovering around these assumed values, may not be the essential contributors to FF progressive success.

However, underlying all the assumptions of POW compensation is a fundamental tenant about the accuracy/appropriateness of the refraction.  Here lies, IMHO, the biggest potential derailment about the optical calculated arguements: Refractionist discretion and the essential lack of quality time that today's insuranced-based eye exams mandate in order for an eyecare business to live and survive.

Darryl's (and others) global  iteration/optimization, however, is another thing entirely.

IMHO:  It's not that the latest FF progressives are oh so good.  It's that the traditional progressives, combined with less than terrrific refractions, and a public's appetite for instant gratification, make it so bad.

If you *really* want to see what the optical promise and advancement is with the best of today's optimized FF lenses, try the SV.

You'll be a believer.  Just don't over promise with *any* progressive, FF or not.  

FWIW

Barry

----------


## Uilleann

Well put Barry!  I'd give you a little greenie...but it says I can't.  Guess I was lovin' on ya too much before or somethin.  :shiner:  Still, very well said Mate!  :cheers::cheers::cheers:

----------


## Darryl Meister

> So, even traditiional progressives has "assumed/default" values for the intended design's position of wear. In this way, I agree with Mike the these values, hovering around these assumed values, may not be the essential contributors to FF progressive success.


You would be surprised how many traditional progressive lenses _are not_ optically optimized for an assumed position of wear. Since most eye care professionals still expect to measure the prescribed powers correctly in a _focimeter_, this optimization is typically constrained significantly in the central viewing zones at the distance and near checking points, if it is applied at all. And, of course, these calculations must assume a single lens power for each base curve in traditional lenses.

----------


## Barry Santini

Thanks again, Darryl, for your input.

It would seem that we ECPs have trained everyone, (including ourselves) to place too much emphasis on focimtery-verification of lenses.

I ask:  Just whom does this (misplaced?) emphasis serve?

Us....

or the patient?

Discussion

Barry

----------


## TLG

> It´s more easy to sell a history than explain the philosophy behind the lenses
> 
> 
> After 4 pages of posts, I must say that I agree completely.


This has been a great thread (mostly) and _this_ is REALLY funny.

----------


## HarryChiling

> I for one would still like to see an answer to this question.


According to patent# 7,322,696 B2, the simple answer Yes.  The gaze angles and the power profile are taken into consideration before the design is computed.  This guy mentions and I will mention that I provide this product but I don't speak for Shamir so if there are any inconsistencies in what I say they are mine not Shamir's.  Great product and technologically advanced, I would still stand by the two most advanced lenses on the market today are the Zeiss Individual and the Shamir Autograph II.

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## Darryl Meister

> According to patent# 7,322,696 B2, the simple answer Yes. The gaze angles and the power profile are taken into consideration before the design is computed.


This patent application doesn't describe a method of optically customizing a lens for the prescription and position of wear. Instead, it describes a method of customizing the addition power profile of a lens for different "viewing environments," so that you could have a lens with more near vision emphasis for office environments, for instance. Most of the major players have been working on this sort of concept for a few years now (e.g., Rodenstock FreeSign, SOLAOne Ego, etcetera).

----------


## Mr.Powers

If you want seam smart. take the simple, and make it hard.

(Piet Hein) 

(Sorry for by bad english)

its sad to see the ( theoredical ) fighting for the right to be smarter than the rest off us, theres a great difrence betwen, theoredical and pratice you dont see shoes come ind size 9,54721. you dont mesure peopels hight in nanometers. or say his PD is 64,35987621 mm, its mabey correct but there are mesurdment in this world that can be mesured but not make any difference in real life:hammer:

in januar last year my office had a sale,
 we sold 43 pairs of indeviduels all whit the helps off the RVT Zeiss lent us.

14 of them complaint the first 3 we tryid to sent to on to Zeiss rep
they gave us 3 new pair off lenses for those custemers. 

2 of them stil complaint, ( i stopt to trust that product) :angry: i ordert Creation for the rest of the custemers that having being complaining, and theres was no problems whit any of them.

KISS = Keep it Simple Stupid

best regards

Peter

----------


## OCP

> If you want seam smart. take the simple, and make it hard.
> 
> (Piet Hein) 
> 
> (Sorry for by bad english)
> 
> its sad to see the ( theoredical ) fighting for the right to be smarter than the rest off us, theres a great difrence betwen, theoredical and pratice you dont see shoes come ind size 9,54721. you dont mesure peopels hight in nanometers. or say his PD is 64,35987621 mm, its mabey correct but there are mesurdment in this world that can be mesured but not make any difference in real life:hammer:
> 
> in januar last year my office had a sale,
> ...


Great answer Peter. :cheers:
I guess this three pairs of lenses was THE lenses that turned Zeiss succes rate from 100% to 99.20 %. ?

Thanks.

Mike

----------


## Laurie

Hello Again,

Hope everyone had a fun and safe New Year celebration!

Back to topic, do pow/as-worn measurements matter?

I agree that VD probably doesn't have a big impact with low Rx's. Lens/Frame curvature matters, as does tilt...how much? Our patients and clients will let us know soon enough. I believe it has enough impact to make the switch.

Darryl, thanks for your note, best wishes for you and your family as well. : ) I've sent your question to the techs for exact clarification...as it is the holiday season, I don't expect an answer right away. However, I did speak to a lab rep where they do tons of personalized back surface ff, and it is also their understanding, that, when pow/as-worn data is given, and when the frame is sent in for tracing, the software changes the algorythyms (sp?), and the design changes (i.e. the placement of the near zone along the convergence path, handling aberrations, ect). This is one of the reasons it is difficult to show rotlex topographies of this classification of lenses, as each is unique depending on frame/patient/rx parameters. 

Fezzy, I hope I was not included in your list of 'all education is biased', as I try really really hard, during CE seminars, to stick to science, not marketing. And, in my classroom (Go HCC!), brands are NEVER mentioned...only technologies.

So....are we all flying around on kites, or is this new way of making PALs and SV, personalized, back-surface FF lenses the wave of the future? I'll place my bets on the latter.

: )

Laurie

----------


## Darryl Meister

> Back to topic, do pow/as-worn measurements matter?


Yes, I do find it odd, and a little discouraging, that certain Shamir distributors in this thread seem to focus more on bashing Carl Zeiss Vision than on discussing the merits of the optical principles involved. In fact, another thread has been started in this forum solely for that purpose.




> I ordered Creation for the rest of the custemers that having being complaining, and theres was no problems whit any of them. KISS = Keep it Simple Stupid


Since Creation is a traditional semi-finished lens, I can essentially summarize the opinions of at least two Shamir customers in this thread as follows:
Limited customization is better than full customization
No customization is better than any customization

If either of you would prefer to continue offering only traditional progressive lens designs to your patients, instead of the latest-generation lens designs, that is certainly your prerogative. I'm not sure why you feel the need to keep comparing your products specifically to Zeiss Individual, however.

I also do not doubt that some customers may feel that "keeping it simple" is more in line with their particular business strategy, which is why most major free-form lens suppliers, including Carl Zeiss Vision, make simplified free-form lens solutions available.




> we sold 43 pairs of indeviduels all whit the helps off the RVT Zeiss lent us. 14 of them complaint


After 20 years in the business, I cannot say that I have ever seen an eyecare professional run into a 33% (14/43) non-adapt rate for _any_ progressive lens. This is indicative of a much greater underlying problem than simple progressive lens acceptance.

While I would encourage you to use products that have only been successful for you, I would certainly like to know the location of the Carl Zeiss Vision lab that you have been using, since you are obviously not using a lab here in the US. I can have someone in your region follow up with the lab to isolate the source of the problem. I look forward to your post.




> I've sent your question to the techs for exact clarification...However, I did speak to a lab rep where they do tons of personalized back surface ff, and it is also their understanding


After some of the rather anecdotal comments regarding the use of this technology by different manufacturers, I think clarification from a person responsible for the implementation of this technology within the actual company would be best. I have already seen several several comments that I know to be invalid, so I would encourage more "definitive" answers whenever possible.




> This is one of the reasons it is difficult to show rotlex topographies of this classification of lenses, as each is unique depending on frame/patient/rx parameters


This is correct; you would need to analyze the lens using optical ray tracing for the position of wear to assess optical performance in this case, which would rely on measuring the refractive action of both surfaces and reconstructing the lens mathematically.

----------


## OCP

> Yes, I do find it odd, and a little discouraging, that certain Shamir distributors in this thread seem to focus more on bashing Carl Zeiss Vision than on discussing the merits of the optical principles involved. In fact, they seem to have started another thread in this forum solely for that purpose.
> 
> 
> Since Creation is a traditional semi-finished lens, I can essentially summarize the opinions of at least two Shamir customers in this thread as follows:
> Limited customization is better than full customization
> No customization is better than any customization
> 
> If either of you would prefer to continue offering only traditional progressive lens designs to your patients, instead of the latest-generation lens designs, that is certainly your prerogative. I'm not sure why you feel the need to keep comparing your products specifically to Zeiss Individual, however.
> 
> ...


First of all I´m not bashing Carl Zeiss or Individual at all. Please feel free to tell me where I do that. I certainly know that bashing other products only give me mail from the moderators to stop the bashing, and with my years of great interest for progressive lenses, this is actually the only and one forum in the world where we can discuss this stuff. I would prefer to be a member of this.

It´s  obvious that there is people reading here, that do not find Individual as the best progressive lens out there (just as Auto II, Impression and all the rest). I guess this forum is for all stances and not only for the PRO Zeiss people? Please correct me if I´m wrong.
As I say ones again, Individual is not a bad lens, but to get back to my point, Vertex and panto is not FIXED values and are nearly impossible to measure correct, and therefore I did only said, that these two measures should be standardize or removed. I know, from a personal view, that some times Creation works better than Individual. I guess this is because of wrong measurements of the Individual, but if that is the case, it will only confirm that some measures are dangerous to measure when you cant do it well enough, and because the measurement are not fixed.
Please just accept this standpoint.

I know for sure, that other here are thinking the same.
They, and I do not have the problem. The manufacturer does.
Not saying Zeiss is the only one. I say the INDUSTRY has the problem.

Actually I know Peter from the thread above, but he are selling not only Shamir lenses. He are, as I know, selling both Zeiss, Hoya and Essilor as well, but his statement is actually very relevant in this thread.

Mike

----------


## OCP

[QUOTE=Darryl Meister;325683]bYes, I do find it odd, and a little discouraging, that certain Shamir distributors in this thread seem to focus more on bashing Carl Zeiss Vision than on discussing the merits of the optical principles involved. In fact, they seem to have started another thread in this forum solely for that purpose.
QUOTE]

Actually I must say, this is very untruthful.
This statement only confirm that this forum is reserved the PRO zeiss people.
In the name of education, I hope this is not true.

Mike

----------


## Darryl Meister

> First of all I´m not bashing Carl Zeiss or Individual at all. Please feel free to tell me where I do that.


Here is a short list, to get started:
Example
Example
Example
Example
Example

There is an underlying implication in just about every one of your posts in this thread that manufactuers who offer forms of customization that differ from Shamir's are somehow offering substandard products and generally attempting to mislead eye care professionals. Even the title of your thread is essentially an accusation to this effect.

To that end, you have mispresented several facts in this thread and, as of late, you have resorted to singling Zeiss Individual out with rather questionable comments regarding its performance.




> I certainly know that bashing other products only give me mail from the moderators to stop the bashing


I am afraid that you seem to "know" many things that simply aren't correct. Assuming that you are acting within our posting guidelines, we (the moderators) are not going to require you to stop "bashing" a product or otherwise expressing deleterious remarks directed at another company or product. In fact, a few of our longstanding members even seem to make a hobby out of bashing certain companies.

While we certainly do not condone such behavior, we attempt to encourage open, respectful communication as much as possible.




> this is actually the only and one forum in the world where we can discuss this stuff... I guess this forum is for all stances and not only for the PRO Zeiss people? Please correct me if I´m wrong.[/


OptiBoard is open to members of all opinions and financial affiliations. Nevertheless, as one of the earliest OptiBoard members on this forum, I can assure you that the success of OptiBoard has never been due to members attempting to advance the products or services of any one individual company.

As for your continued insinuations that OptiBoard caters to "pro ZEISS" people, which any longstanding member would know is silly, you have actually mentioned ZEISS products more often in your posts than any "ZEISS" person. Usually in the context of how they compare to your own products. I, personally, keep asking you to stick to the principles, not the products.

Further, I would encourage any member who would like to endorse their products and services outside the context of relevant discussion to sponsor a banner ad on this site, which has the added advantage of providing financial support to maintain OptiBoard for all members to enjoy.




> I know, from a personal view, that some times Creation works better than Individual.


Once again, you are singling out a ZEISS product in the context of your own.




> I guess this is because of wrong measurements of the Individual, but if that is the case, it will only confirm that some measures are dangerous to measure when you cant do it well enough, and because the measurement are not fixed.


I agree that submitting "bad" position of wear measurements can negatively influence optical performance. However...

Wearer preference is not based solely on the presence or absence of position of wear measurements. There is every possibility that some progressive lens wearers may simply prefer the Creation lens design more, particularly when optical customization is less significant, although I have seen evidence from _independent clinical studies_ to suggest otherwise.

Also, optical performance is no more sensitive to position of wear measurements, and in some cases even less sensitive, than it is to any other fitting measurement, including the PD and fitting height.




> As I say ones again, Individual is not a bad lens, but to get back to my point, Vertex and panto is not FIXED values and are nearly impossible to measure correct


Yes, you can negatively influence optical performance by supplying the incorrect position of wear measurements, just as you can negatively influence performance by not measuring PDs or fitting heights correctly. But you continue to fail to realize that _submitting incorrect_ position of wear measurements will not impact optical performance any more than _not submitting_ position of wear measurements when there is a comparable difference between the geometry of the fitted lenses versus the geometry of the refracted lenses.

*But, more to the point, wouldn't your patients be better served by learning to take these position of wear measurements more accurately rather than by resorting to traditional lens designs based on technology that hasn't changed fundamentally in over 50 years?*




> Actually I know Peter from the thread above, but he are selling not only Shamir lenses. He are, as I know, selling both Zeiss, Hoya and Essilor as well, but his statement is actually very relevant in this thread.


Yes, I got the impression that you two knew each other. His last few posts, however, have made no mention of recommending any lens other than Shamir products.

----------


## Mr.Powers

post

----------


## obxeyeguy

[QUOTE=OCP;325693]


> bYes, I do find it odd, and a little discouraging, that certain Shamir distributors in this thread seem to focus more on bashing Carl Zeiss Vision than on discussing the merits of the optical principles involved. In fact, they seem to have started another thread in this forum solely for that purpose.
> QUOTE]
> 
> Actually I must say, this is very untruthful.
> This statement only confirm that this forum is reserved the PRO zeiss people.
> In the name of education, I hope this is not true.
> 
> Mike





> If you are stating that they re-design each lens based upon the prescription and position of wear measurements, as opposed to simply compensating the prescription for lens tilt, this is actually a pretty significant claim. And certainly at odds with some of Mike's statements. Have any of the technical guys at Shamir ever actually confirmed this for you?





> I for one would still like to see an answer to this question.


First off, I do not sell Zeiss lenses but found this question by Darryl to be quite interesting, yet you failed to answer it once already (oversight?). Now you acuse us of all being "pro Zeiss", which I can assure you is hardly the case, but we are here to learn the differences in all lenses.

So, is in fact, the Autograph lens re-designed for all the measurements or just simply power compensated. A simple Yes or No works here, and adds immensely to your credibility in this debate, as otherwise it's just inuendo.  Step up, or move on.

----------


## Darryl Meister

> Actually I must say, this is very untruthful.


That was certainly how I interpreted your comments in the new thread, which essentially rehashes half of this thread. Allow me to quote you:

_...agree that Individual, theorethical and hypothetical, could be the best lens out there, but thats because we are only familar with the data we read on the paper from the manufacturer... In the name of evolution, the manufacturer will keep on invent new "histories" to sell new lenses and to provide new and more complicated data to produce the lenses. In my opinion this is mostly bulls***... (-and I claim Shamir are handling the abberations best :D and we don´t tell imaginary stories as well)_

I do agree, however, that Carl Zeiss Vision has provided a lot of "data on paper" for Individual. I would encourage all manufacturers to fully disclose the features of their products by making the necessary substantiation of their product claims available to eyecare professionals so that they can make a well-informed purchase decision.




> This statement only confirm that this forum is reserved the PRO zeiss people.


Mike, please feel free to attempt to find another thread on OptiBoard started by a "pro ZEISS" person that promotes a ZEISS product, makes disparaging remarks regarding the performance of a non-ZEISS product, misrepresents optical principles to support a ZEISS product, etcetera.




> Pleas let me hear from somebody that fell they have at ingreasede costumers satisfaction whit Zeiss Individual i like to learn what I and my co. workers are doing wrong !


Again, it would be best for you to provide (e-mail or PM is fine) the name or location of your laboratory. I would be happy to make the appropriate ZEISS representative in your region aware of your situation.

Unfortunately, if you have had non-adapts with 14 out of 43 Individual jobs, it is unlikely that you will solve the problem simply by reading OptiBoard posts. This is indicative of a significant issue that will probably need to be addressed in person or resolved at the laboratory level.

Further, if you do indeed want to continue selling ZEISS lenses, but are concerned about taking position of wear measurements, GT2 3D should be available in your area. This is a customized lens that does not require position of wear measurements. And, of course, traditional ZEISS progressive lenses are also still available.

----------


## Mr.Powers

still like to hear from somebody, about my last post !

----------


## Darryl Meister

Since this thread has unfortunately degenerated into a lot of "us versus them" bantering that is unnecessarily focused on specific products, I wanted to do my part to get this back on topic.

Product endorsements aside, Mike's (OCP's) contention, at least as I understand it, is essentially that position of wear measurements cause more trouble than they are worth because:

1. These measurements are difficult to measure accurately.

2. Bad measurements can negatively influence optical performance.

3. These measurements may change because they are not "fixed."

His conclusion seems to be that you are better off selling lenses that do not rely on position of wear measurements or that at least rely on some simplified version of these measurements.

Mike, please correct me if I have misunderstood any of these points, before I continue.

Also remember that no free-form lens supplier _requires_ position of wear measurements. Even Zeiss Individual can be ordered without them, resulting in a lens design that is optically customized for a "default" position of wear, if you would prefer not to take these measurements.

----------


## OCP

> Since this thread has unfortunately degenerated into a lot of "us versus them" bantering that is unnecessarily focused on specific products, I wanted to do my part to get this back on topic.
> 
> Product endorsements aside, Mike's (OCP's) contention, at least as I understand it, is essentially that position of wear measurements cause more trouble than they are worth because:
> 
> 1. These measurements are difficult to measure accurately.
> 
> 2. Bad measurements can negatively influence optical performance.
> 
> 3. These measurements may change because they are not "fixed."
> ...


Hi Darryl.

Your three point seems correct.
Vertex and Panto is the questionable measures here, and because these measures do not noticeable impact the optical result, I suggest the industry use default or simplified these two measures. I will explain ones again, why these two measures should be simplyfied, or removed, and why they are not fixed values. 
*Panto*: You change head angle many times a day and your eye does not move vertical on a line, but from the same attached point. That will change the angle. Panto value are normally from 5-15 degrees, and therefore it would be more logical to use only 3 parameters for this, lets say 5-10-15. Then you can only go 2-3 degrees wrong and 2-3 degrees will not impact the optical design at all.
*Vertex*: You or someone else said that 13½ mm vertex was more correct than 13 mm. That statement is again only theoretical because the groove can easily move the lens 1-2-3 mm back or forwards. Only very few can measure this value 100 % correct. It´s nearly impossible. We know, that if you dont have the refracted AND the fitted vertex you cant make POW compensation, but you can always make *design* compensating (design compensation does not include power changing in the vision area. Only in the abberations zones), but again this is more theoretical in my opinion. The manufacturer will always seek the best optical solution, and that include large vision area on near, intermedia and distance, so my point is, if you with 13½ mm vertex can make the best possible design with the largest vision area, why dont use that design in 10 mm Vertex as well.? It´s not logical not to use that design no matter what the Vertex are. I know you can increase the astigmatical deviation if you put the lens closer to the eye (and I must think that is what happens), but if you measure wrong, lets say you measure 7 mm and in real life after glazing etc, the Vertex are 13 mm, then the client would actually get a harder design than they are used to and therefore get adaption issues. I´m quite sure this is the most frequent reason for adaption issues. Normally vertex distances goes from 9-15 I think. By using default (12-13) you will mostly only have 2-3 mm wrong vertex, and 2-3 mm wrong Vertex does not influence the design noticeable at all.

When saying that it´s only a question about education, this is a truth with modifications. When using only a few parametres here, you can actually simplify the tools for the measurements and then you don´t need the education in the such a degree. 

I hope this ones again could clear out my stance on these two parameters.

And please. When I say "you" I nessasary dont meen Individual or Zeiss. I´m talking about the industry in general. But you are representative for Zeiss so it will be more accurate to talk to you about Individual. I´m not bashing your product at all. Only talk about it.

Mike

----------


## OCP

[QUOTE=obxeyeguy;325705]


> First off, I do not sell Zeiss lenses but found this question by Darryl to be quite interesting, yet you failed to answer it once already (oversight?). Now you acuse us of all being "pro Zeiss", which I can assure you is hardly the case, but we are here to learn the differences in all lenses.
> 
> So, is in fact, the Autograph lens re-designed for all the measurements or just simply power compensated. A simple Yes or No works here, and adds immensely to your credibility in this debate, as otherwise it's just inuendo. Step up, or move on.


Instead of just looking for something to blaim me, you could start to join the debate with some constructive informations.

Where did I blame you for be a Pro-Zeiss member ? Cant you read, or at least read between the lines?

This is not a debate about what Zeiss or Shamir are doing right or wrong.

Mike

----------


## obxeyeguy

[QUOTE=OCP;325748]


> Instead of just looking for something to blaim me, you could start to join the debate with some constructive informations.
> 
> Where did I blame you for be a Pro-Zeiss member ? Cant you read, or at least read between the lines?
> 
> This is not a debate about what Zeiss or Shamir are doing right or wrong.
> 
> Mike


Another typical response, but still no answer.  Throw it out, see what sticks but nothing to back it up.

----------


## OCP

[QUOTE=obxeyeguy;325753]


> Another typical response, but still no answer. Throw it out, see what sticks but nothing to back it up.


You do not realy get it, do you?

Why do you want a answer from me of something I find silly.?
Why dont you ask your Shamir representative if this is *so* important for you?
Why dont you bring something informative to this debate instead of trying to drag me down.? You can´t.


Mike

----------


## YrahG

_In the name of evolution, the manufacturer will keep on invent new "histories" to sell new lenses and to provide new and more complicated data to produce the lenses. In my opinion this is mostly bulls***... (-and I claim Shamir are handling the abberations best :D and we don´t tell imaginary stories as well)_


Wow are we really claiming that Zeiss does not provide accurate data?  I personally wish that all manufaturers includeing Shamir released white paper such as Zeiss.  I would go so far as to say Zeiss's white paper could be used as a template for other companies since it is often thorough and contains all information necessary by me with exception to the stuff that would probably be overkill.  Darryl once again I appreciate all your company has done and will do to provide accurate and concise information, I tend to go searching for information and I am sure I don't have to tell you it isn't easy to come across.  Once again let me reiterate, the Zeiss Individual is a top notch lens and despite what the Shamir fans opening and inserting foot in mouth I think the Auto II is the same.

----------


## OCP

> _In the name of evolution, the manufacturer will keep on invent new "histories" to sell new lenses and to provide new and more complicated data to produce the lenses. In my opinion this is mostly bulls***... (-and I claim Shamir are handling the abberations best :D and we don´t tell imaginary stories as well)_
> 
> 
> Wow are we really claiming that Zeiss does not provide accurate data? I personally wish that all manufaturers includeing Shamir released white paper such as Zeiss. I would go so far as to say Zeiss's white paper could be used as a template for other companies since it is often thorough and contains all information necessary by me with exception to the stuff that would probably be overkill. Darryl once again I appreciate all your company has done and will do to provide accurate and concise information, I tend to go searching for information and I am sure I don't have to tell you it isn't easy to come across. Once again let me reiterate, the Zeiss Individual is a top notch lens and despite what the Shamir fans opening and inserting foot in mouth I think the Auto II is the same.


Someone likes white paper, others never read it. I agree that if someone read it, the white paper from Zeiss is a great one even though it is technically and theoretical stuff. 
My english is not great as other here, so I apologize if someone got that understanding that I wrote that Zeiss not provide accurate data. (even I cant see why someone got that understanding). Please try to bear with our overseas different language, thanks. I prefer to debate with you, in spite of language issues, instead of just shut up. We are all here for learning, and excuse me, I think there is plenty of room here for both mathematician, and optician wholesaler with controversial stances. 

That makes it just more funny to join. :cheers:

Mike

----------


## Barry Santini

> Hi Darryl.
> 
> 
> *Panto*: You change head angle many times a day and your eye does not move vertical on a line, but from the same attached point. That will change the angle. Panto value are normally from 5-15 degrees, and therefore it would be more logical to use only 3 parameters for this, lets say 5-10-15. Then you can only go 2-3 degrees wrong and 2-3 degrees will not impact the optical design at all.
> 
> *Vertex*: You or someone else said that 13½ mm vertex was more correct than 13 mm. That statement is again only theoretical because the groove can easily move the lens 1-2-3 mm back or forwards. Only very few can measure this value 100 % correct. It´s nearly impossible. We know, that if you dont have the refracted AND the fitted vertex you cant make POW compensation, but you can always make *design* compensating (design compensation does not include power changing in the vision area. Only in the abberations zones), but again this is more theoretical in my opinion. The manufacturer will always seek the best optical solution, and that include large vision area on near, intermedia and distance, so my point is, if you with 13½ mm vertex can make the best possible design with the largest vision area, why dont use that design in 10 mm Vertex as well.? It´s not logical not to use that design no matter what the Vertex are. I know you can increase the astigmatical deviation if you put the lens closer to the eye (and I must think that is what happens), but if you measure wrong, lets say you measure 7 mm and in real life after glazing etc, the Vertex are 13 mm, then the client would actually get a harder design than they are used to and therefore get adaption issues. I´m quite sure this is the most frequent reason for adaption issues. Normally vertex distances goes from 9-15 I think. By using default (12-13) you will mostly only have 2-3 mm wrong vertex, and 2-3 mm wrong Vertex does not influence the design noticeable at all. 
> Mike


I used to share your observations about pantoscopic tilt, Mike.
But then, this forum and Darryl & Laurie in particular set me straight:

Panto is NOT about head/face angle. It's about determining how to best ensure the design pole of a lens intersects the center of rotation of the eye.
Therefore, it's about ensuring that a client's head/face plane is in an erect position (NOT the habitual position of the client's head or facial plane posture, and not the various head angles that a person sweeps through posturally in a day. That's taken care of when it's all lined up properly with the CR).

As far as vertex - for me it's about the larger deviations from default values and how it effects apparent FOV (field of view). I would expect an advanced design would incorporate this value into their DV optimzation..._regardless of power_.

FWIW

Barry

----------


## obxeyeguy

> If you are stating that they re-design each lens based upon the prescription and position of wear measurements, as opposed to simply compensating the prescription for lens tilt, this is actually a pretty significant claim. And certainly at odds with some of Mike's statements. Have any of the technical guys at Shamir ever actually confirmed this for you?


[QUOTE=OCP;325807]


> You do not realy get it, do you?
> 
> Why do you want a answer from me of something I find silly.?Which is the above question, as you have skipped it twice now.
> Why dont you ask your Shamir representative if this is *so* important for you? Because your here representing them to be the best and you seem to have all the answers.
> Why dont you bring something informative to this debate instead of trying to drag me down.? You can´t. I could care less about dragging you down, as you seem to be doing fine on your own. 
> 
> Mike


Mike, I'm sure you are a very smart guy, but the way you come across is your way or the highway, nothing else. Go back and re-read some of you own posts, and whenever you get questioned on anything, all we get is a song and a dance. 

Oh, buy the way, as I find it to be very relevant to the conversation, as maybe others do also, the question still stands.

(insert cocky response here)

Strike three!!

----------


## OCP

> I used to share your observations about pantoscopic tilt, Mike.
> But then, this forum and Darryl & Laurie in particular set me straight:
> 
> Panto is NOT about head/face angle. It's about determining how to best ensure the design pole of a lens intersects the center of rotation of the eye.
> Therefore, it's about ensuring that a client's head/face plane is in an erect position (NOT the habitual position of the client's head or facial plane posture, and not the various head angles that a person sweeps through posturally in a day. That's taken care of when it's all lined up properly with the CR).
> 
> As far as vertex - for me it's about the larger deviations from default values and how it effects apparent FOV (field of view). I would expect an advanced design would incorporate this value into their DV optimzation..._regardless of power_.
> 
> FWIW
> ...


Hi Barry.

About Panto you are so right.
"Panto is NOT about head/face angle. It's about determining how to best ensure the design pole of a lens intersects the center of rotation of the eye."
BUT if you move your head a littlte bit up and down, you change the result of the measure!
SO the Panto is only a average measure where you presume this is the avarage head position for your client. 
Now we are back to where we startet. Many of us are always seeking to make the best possible lens for our client, by taking a lot of measures (that many times goes wrong) and some of these measures are actually only average values. Thats why I suggest to standardise these mesurements to avoid wrong measurements. I tell you that the Panto tilt is very, very difficult to measure correct for many reasons. The client do not always stand normally with relaxed head position, and the tools you use to measure the result is inaccurate.

Mike

----------


## OCP

[QUOTE=obxeyeguy;325843]


> Mike, I'm sure you are a very smart guy, but the way you come across is your way or the highway, nothing else. Go back and re-read some of you own posts, and whenever you get questioned on anything, all we get is a song and a dance. 
> 
> Oh, buy the way, as I find it to be very relevant to the conversation, as maybe others do also, the question still stands.
> 
> (insert cocky response here)
> 
> Strike three!!


Well I only defend my right to disagree with the majority in a issue that most of you was not aware of.

Mike

----------


## Barry Santini

> Hi Barry.
> 
> About Panto you are so right.
> "Panto is NOT about head/face angle. It's about determining how to best ensure the design pole of a lens intersects the center of rotation of the eye."
> BUT if you move your head a littlte bit up and down, you change the result of the measure!
> SO the Panto is only a average measure where you presume this is the avarage head position for your client. 
> Now we are back to where we startet. Many of us are always seeking to make the best possible lens for our client, by taking a lot of measures (that many times goes wrong) and some of these measures are actually only average values. Thats why I suggest to standardise these mesurements to avoid wrong measurements. I tell you that the Panto tilt is very, very difficult to measure correct for many reasons. The clients do not always stand normally with relaxed head position, and the tools you use to measure the result is inaccurate.
> 
> Mike


I'd like to verbalize the assumptions I understand are currently being used to determine pantoscopic tilt:

1. The goal is to get the design (reference) pole of the lens being fitted to intersect the CR of the eye. In the case of best form fitted, spherically-based, corrected-curve lenses, the OC and the *design* pole are one and the same. Therefore, Martin's rule of tilt (which assumes a vertex distance I believe, of 13.5 to 14mm (27mm to the CR) applies when fitting these lenses.

2. A method of measuring pantoscopic tilt starts with the client's facila plane in an "upright" position.  To determine the facila plane, iimagine a line drawn from the upper orbital bone to the lower orbital bone, and continue downward to the plane of the teeth and chin. In many cases, the points described will not lie all in a single plane.  So you average.

3. Client preference in frame fitting will further help to determine the final anle of the frame/lens plane.  So eyewear should be pre-fiited as much as possible *before* a measurement is made.

4. Ear height and habitual head or nech posture should only influence your placement of multifocal lenses, bifocal, tri, or progressives, depending on the "in-situ" resultant frame fit and plane.  This should not and does not influence the results of 1, 2, or 3.

So yeah Mike, It's a fudge.  And I'm here to say the my own overwhelming success with Auto II SV, which does NOT require Panto, Vertex or FF (within a range up to 8 degress I believe) values, is a testament to the simplified fitting process.  My only complaint with Shamir is that they don't clearly compose, explain and communicate the proper fitting instructions for Auto II SV.

So What would I like beyond the simplicity of Auto II SV?  I'd like the ability for some fits, as Individual SV allows, to specify the specific Base Curve to be used.  In this way, I get the lense plane to match the frame plane, and the fit of the eyewear is more correctkly ensures, particularly with the nutty zyl frames being made today.


Further *constructive* discussion...from anyone...

_Buelller?_

Barry

----------


## OCP

> I'd like to verbalize the assumptions I understand are currently being used to determine pantoscopic tilt:
> 
> 1. The goal is to get the design (reference) pole of the lens being fitted to intersect the CR of the eye. In the case of best form fitted, spherically-based, corrected-curve lenses, the OC and the *design* pole are one and the same. Therefore, Martin's rule of tilt (which assumes a vertex distance I believe, of 13.5 to 14mm (27mm to the CR) applies when fitting these lenses.
> 
> 2. A method of measuring pantoscopic tilt starts with the client's facila plane in an "upright" position. To determine the facila plane, iimagine a line drawn from the upper orbital bone to the lower orbital bone, and continue downward to the plane of the teeth and chin. In many cases, the points described will not lie all in a single plane. So you average.
> 
> 3. Client preference in frame fitting will further help to determine the final anle of the frame/lens plane. So eyewear should be pre-fiited as much as possible *before* a measurement is made.
> 
> 4. Ear height and habitual head or nech posture should only influence your placement of multifocal lenses, bifocal, tri, or progressives, depending on the "in-situ" resultant frame fit and plane. This should not and does not influence the results of 1, 2, or 3.
> ...


Hi Barry

Without being 100 % sure, I think the strategy from Shamir, accordance to SMART SV, is to use this lenses for normal frames (frame angle up to 8 degree) and use the Attitude family for curves more than this.

SMART SV, with standard measures, is really a great succes. 
Anyway, I agree that it would be desirable if we could order SMART SV with FaceForm angle as well.

About the panto tilt I do not, in the theory, disagree with you. We are back to the beginning again, where it´s nearly imposible to measure this tilt perfect every time. This only confirm the need for a more easy way to measure the angle, and three different values is actually enough, to get a acceptable result. With SMART SV you have a great succes with only one value. -and a standard one as well. 
Mike

----------


## Darryl Meister

Mike, let me address your three concerns individually, although I will be repeating myself in most cases. Unfortunately, there are several principles that you still do not seem to understand clearly. Hopefully, this post will clarify at least some of these misconceptions.




> *Panto*: You change head angle many times a day and your eye does not move vertical on a line, but from the same attached point. That will change the angle.


As Barry reiterated, pantoscopic tilt does not change with either head or eye angle. Panto will only change in a finished pair of eyeglasses if the actual position of the eyeglasses on the face is physically moved. You are mistaking the angle that the lens makes with the line of sight at different viewing positions for the pantoscopic angle used in lens design calculations, which is actually used to predict the angle of the line of sight at these positions.




> Panto value are normally from 5-15 degrees, and therefore it would be more logical to use only 3 parameters for this, lets say 5-10-15. Then you can only go 2-3 degrees wrong and 2-3 degrees will not impact the optical design at all.


It is does not follow (that is, your argument is non sequitur) that it is "more logical" to use only 3 pantoscopic tilt options. Even if we assume that an error of 2.5 deg is acceptable, you are still no more likely to choose the best option of the 3 available angles unless you can estimate the angle of tilt within 2.5 deg in the first place. So what have you gained?

I will provide you with a very clear example: If you can only estimate this angle within +/-4 deg, for instance, and the real value is 5 deg, you could still potentially guess "9 deg" (5 + 4 = 9). You would then choose the 10 deg design option, which is still 5 deg off from the best design option (that is, the 5 deg design).

In fact, if you _can_ take these measurements accurately, you are only increasing the likelihood of an error, since you have an inherent rounding error of up to 2.5 deg from the exact value.

I also noticed that you didn't mention wrap, although the optics of progressive lenses similarly affected by both pantoscopic tilt and face-form wrap. Further, only lens designs that are truly optimized for the position of wear will adequately address the effects of either type of lens tilt.




> 1. These measurements are difficult to measure accurately.


I agree that taking these measurements accurately does indeed involve a "learning curve" for many opticians. Of course, taking PD and fitting height measurements accurately also involves a learning curve for new opticians.

Those eye care professionals who want to offer their patients the best vision quality possible will be more willing to embrace these new technologies, even if they require additional training.

Further, new tools are becoming available every day that allow eye care professionals to take these measurements with greater accuracy and increasing ease.




> 2. Bad measurements can negatively influence optical performance.


Again, taking "no" measurements will often result in the exact same errors in optical performance compared to taking "bad" measurements.




> 3. These measurements may change because they are not "fixed."


Most of these measurements are indeed fixed, at least to the extent that the patient wears his or her eyeglasses in roughly the same place on the face. As I mentioned above, you have simply misunderstand the application of pantoscopic tilt in lens design.




> You or someone else said that 13½ mm vertex was more correct than 13 mm. That statement is again only theoretical because the groove can easily move the lens 1-2-3 mm back or forwards. Only very few can measure this value 100 % correct. It´s nearly impossible.


As I have already explained, it does not matter whether you can measure this or any other position of wear value to an accuracy of 100%. Unless you are completely off in your measurement, you will still arrive at a value that will often be closer to the actual value than you would obtain by ignoring this measurement entirely.

In simpler terms, your argument isn't entirely unlike saying that, because someone isn't necessarily very good at his job, he shouldn't bother working at all. Unless you are so bad at your job that you are actually doing more harm than good, you'd probably want to earn a living though.




> We know, that if you dont have the refracted AND the fitted vertex you cant make POW compensation


You still don't seem to comprehend the difference between _compensating a prescription_ for vertex distance versus _optimizing a lens design_ for the vertex distance associated with the position of wear, which I have already attempted to explain to you several times in this thread.




> but you can always make *design* compensating (design compensation does not include power changing in the vision area. Only in the abberations zones), but again this is more theoretical in my opinion.


You are only making a conjecture here. And it is incorrect. Optimization for the position of wear _primarily_ influences the "vision area," not the "aberration zones." In fact, there is no reason to attempt to nail down the exact prescription for the position of wear within the peripheral zones of a progressive lens _because_ they are aberrated.




> It´s not logical not to use that design no matter what the Vertex are.


I agree that the final lens will never be any better than the best example of the basic lens design (that is, garbage in = garbage out). Customization for the prescription and the position of wear simply preserves the intended optical peformance for each wearer, even if that optical performance is mediocre in the first place.




> but if you measure wrong, lets say you measure 7 mm and in real life after glazing etc, the Vertex are 13 mm, then the client would actually get a harder design than they are used to and therefore get adaption issues.


Let's assume for the sake of argument that could indeed make such a gross measurement error. There is also every possibility that the lens could be fitted a vertex distance of 7 mm, while the semi-finished lens design may have been optimized for an assumed vertex distance of 13 mm, leaving you in the exact same position.




> I´m quite sure this is the most frequent reason for adaption issues.


Then, by necessary extension, you must also agree that accurately optimizing a progressive lens design for these measurements should improve adaptation.




> Normally vertex distances goes from 9-15 I think.


I think that you have chosen an aribtrary range of numbers (9 to 15) based upon your desire to support your belief that you will never be off more than 2 to 3 points from some average value (12 mm), not upon vertex measurements from an actual population of wearers, which can vary significantly based upon the frame size, facial features, prescription, etcetera.

Nevertheless, I agree that the use of judiciously selected "averages" for the position of wear is preferable to taking no measurements at all or to taking measurements that are grossly inaccurate. But I also believe that eyecare professionals _are more than capable_ of taking measurements that are reasonably accurate.




> Someone likes white paper, others never read it.


But they do at least have the choice when a white paper is available. Not everyone reads the nutrition information labels on the food they buy, while many feel that these labels provide very important information.

----------


## OCP

> Mike, let me address your three concerns individually, although I will be repeating myself in most cases. Unfortunately, there are several principles that you still do not seem to understand clearly. Hopefully, this post will clarify at least some of these misconceptions.
> 
> 
> As Barry reiterated, pantoscopic tilt does not change with either head or eye angle. Panto will only change in a finished pair of eyeglasses if the actual position of the eyeglasses on the face is physically moved. You are mistaking the angle that the lens makes with the line of sight at different viewing positions for the pantoscopic angle used in lens design calculations, which is actually used to predict the angle of the line of sight at these positions.
> 
> 
> It is does not follow (that is, your argument is non sequitur) that it is "more logical" to use only 3 pantoscopic tilt options. Even if we assume that an error of 2.5 deg is acceptable, you are still no more likely to choose the best option of the 3 available angles unless you can estimate the angle of tilt within 2.5 deg in the first place. So what have you gained?
> 
> I will provide you with a very clear example: If you can only estimate this angle within +/-4 deg, for instance, and the real value is 5 deg, you could still potentially guess "9 deg" (5 + 4 = 9). You would then choose the 10 deg design option, which is still 5 deg off from the best design option (that is, the 5 deg design).
> ...


Hi Darryl

If you measure panto with the Infral, would the result be equivalent no matter how the patient a standing with their head?

You say that opticians _are more than capable_ to measure Panto and Vertex. This is conjecture as well. Everyone reading here, try to let different opticians in your stores take these measures. I will promise, that you will all get different results, and sometimes the result will be very long away from "reasonably accurate".

I do not know your skills in US, but in Denmark, where we have 4½ years of education, it´s a problem. I´m quite sure the same issues is seen in other countries.

If Panto and Vertex was fixed, the tools to measure these values should be good enough. You claim that they are not and we will se new and better tools. Why? A fixed value is very easy to measure.!

_"You still don't seem to comprehend the difference between compensating a prescription for vertex distance versus optimizing a lens design for the vertex distance associated with the position of wear, which I have already attempted to explain to you several times in this thread._ _Optimization for the position of wear primarily influences the "vision area," not the "aberration zones." In fact, there is no reason to attempt to nail down the exact prescription for the position of wear within the peripheral zones of a progressive lens because they are aberrated."_

You read me wrong. Vertex design compensating DO influence the vision area, but not the POWER in the vision area. Pow. compensation is only when you got the refracted Vertex as well. If the Vertex is very short, lets say 7 mm, then it´s acually possible to increase the vision area by increasing the CYL/SPH abberations in the peripheral zones. Thats a fact. Anyway it works great in the theory, because if the Vertex is not 7 mm in real life, but lets say 10 mm or even more, the increased Cyl. Abberations could actually make a worse design than the client are used to.

Everyone here: Please understand that this dialog is not because I´m stubborn (Darryl could just as well be that), but Darryl has a great reputation here and many consider Darryl as the great optical guru, as he certain are in many cases. For me, I look just more and more opinionated, and I know that. I´m alone in the wrong class where everyone agree with the "teacher", and not strong enough to just ignore this thread. Lucky me we are thousandth kilometre from each other, otherwise you would all beat me up in the schoolyard.:hammer:

Mike

----------


## HarryChiling

> Hi Darryl
> 
> If you measure panto with the Infral, would the result be equivalent no matter how the patient a standing with their head?


The panto that is used to compensate the design is to me better thought of as the angle the lens makes with the visual axis, not the angle it makes with the plane perpendicular to the floor.  So as the head moves so to does the eye's and glasses in a stationary group of objects.  The angle compared to the plane perpendicualr to the floor will change, but the glasses will remain relatively stationary in front of the eyes




> You say that opticians _are more than capable_ to measure Panto and Vertex. This is conjecture as well. Everyone reading here, try to let different opticians in your stores take these measures. I will promise, that you will all get different results, and sometimes the result will be very long away from "reasonably accurate".


I think your point here is valid, I am not sure that most opticians are more than capable but a select few are and those are the ones that tend to visit this board so we are lulled into a sense of greater opticians out there as the norm.  Manufacturers have taken this varying degree of education and skill into account though, the lenses can be ordered with vertex, panto, and faceform or not, the accurate measures optimize the design to the pateints particular situation.  Without these measurements "averages" are used to create the lens.  Every lens from the traditional molded designs to the freeform make assumptions that the lens will have a certain degree of tilt panto and faceform and they are designed for a certain vertex distance.  Even single vision designs are designed for a certain vertex distance.




> I do not know your skills in US, but in Denmark, where we have 4½ years of education, it´s a problem. I´m quite sure the same issues is seen in other countries.


Same issues here the measurements can be off from a little to a significant, the reason why more equipment and measureing tools keep coming out.  These lenses are the creme of the crop, this is not conjecture but a majority of PAL non adapts coem from wrong measurements PDs and seg hgts.  Throw in additional measures and you have a point that issues may coem up, but again keep in ind these lenses are not your average ordinary lenses.




> If Panto and Vertex was fixed, the tools to measure these values should be good enough. You claim that they are not and we will se new and better tools. Why? A fixed value is very easy to measure.!


Although the angle the lens makes with the visual axis is fixed the angle the lens makes with the plane perpendicular to the ground is not fixed and this can and does cause error.  While their is room to improve the measureing device education for the measurer is far more simple IMO.  However, the march for improved measureing devices moves forward.




> Everyone here: Please understand that this dialog is not because I´m stubborn (Darryl could just as well be that), but Darryl has a great reputation here and many consider Darryl as the great optical guru, as he certain are in many cases. For me, I look just more and more opinionated, and I know that. I´m alone in the wrong class where everyone agree with the "teacher", and not strong enough to just ignore this thread. Lucky me we are thousandth kilometre from each other, otherwise you would all beat me up in the schoolyard.:hammer:
> 
> Mike


I think when it comes to opinionated I will have to defend my throne, but you can be prince if that suits you.  Darryl has opinions and you have opinions but when it coems to facts they are just that, facts.  I would say Darryl is one of the great optical minds in our country and his ability to share the most complicated subject while trying to avoid bruising ego's is a real show of class.  

Personally, I wouldn't beat you up until after we had a few pints. ;):cheers:

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## Darryl Meister

> If you measure panto with the Infral, would the result be equivalent no matter how the patient a standing with their head?


Because the pantoscopic tilt angle is based upon the line of sight, which should pass through the fitting cross when the eye is in "primary position," deliberately tilting your head can influence the measurement. Patients should maintain their habitual posture during the measurement cycle in order to ensure optimum results.




> You say that opticians _are more than capable_ to measure Panto and Vertex. This is conjecture as well.


Yes, it is conjecture, which is why I preceded the statement with "I believe," instead of concluding the statement with "That's a fact" as you have done after several conjectures.




> Everyone reading here, try to let different opticians in your stores take these measures. I will promise, that you will all get different results, and sometimes the result will be very long away from "reasonably accurate".


Possibly, but only because supplying this measurement represents a fairly new and possibly unfamiliar concept. But with the right tools and training, I am confident that eyecare professionals could take these measurements within a level of accuracy suitable for ordering customized lenses with an improved visual outcome.

Technology continues to evolve in every industry. In my opinion, most eyecare professionals would choose to enhance their skill sets to reflect advancements in clinical care and the current state of the art, given the opportunity.

Besides, you're not really arguing against taking these measurements, you're arguing against taking these measurements using anyone else's method but your own. After all, you seem to be happy to supply pantoscopic tilt angle using Shamir's (?) method of specifying either 5, 10, or 15 deg, which I've already demonstrated is no less prone to errors.




> I do not know your skills in US, but in Denmark, where we have 4½ years of education, it´s a problem.


Are you suggesting that it takes professors in Denmark more than 4½ to teach opticians in Denmark how to measure pantoscopic tilt? Although I do not live in Denmark, I suspect that teaching this measurement simply isn't part of the curriculum at the moment.




> If Panto and Vertex was fixed, the tools to measure these values should be good enough. You claim that they are not


No, I'm afraid that I didn't claim that.




> You read me wrong. Vertex design compensating DO influence the vision area, but not the POWER in the vision area. Pow. compensation is only when you got the refracted Vertex as well. If the Vertex is very short, lets say 7 mm, then it´s acually possible to increase the vision area by increasing the CYL/SPH abberations in the peripheral zones...


I didn't really understand the point in this section. Possibly this is due to a language barrier.

It is difficult to influence vision without influencing power; in fact, it would require either a significant level of high-order aberrations or a media defect, such as scatter from surfacing aberrations. I doubt that you are referring to either though.

In any case, unless you have actually used progressive lens optical design software at some point that is capable of optical optimization for the position of wear, and then compared the results of different lens design scenarios, you may be overstating your knowledge of these effects on lens design.




> Thats a fact.


I would feel considerably more comfortable discussing these matters with you if you were to refrain from referring to everything you say as a "fact." Unfortunately, many of your comments have been rather inaccurate, not factual.




> Anyway it works great in the theory, because if the Vertex is not 7 mm in real life, but lets say 10 mm or even more, the increased Cyl. Abberations could actually make a worse design than the client are used to.


You have made several statements regarding "real life" performance, although these have all been based upon conjecture and your own anecdotal experience. The so-called "theoretical" arguments that I have provided are at least deductive arguments easily proven, regardless of whether the results will be significant enough for all wearers to experience a notable visual difference. Besides, there are already clinical studies available that do indeed detail the "real life" differences among actual wearers.




> Darryl has a great reputation here and many consider Darryl as the great optical guru, as he certain are in many cases.


I would attribute any positive reputation I may have in this industry to a genuine desire to learn and share as much as possible with an open, objective mind. After all, we're all in this together.




> For me, I look just more and more opinionated, and I know that. I´m alone in the wrong class where everyone agree with the "teacher", and not strong enough to just ignore this thread.


Mike, if everyone agrees with me, it is only because I have provided sound deductive arguments, numerical examples, contour plots, etcetera. You, on the other hand, have unfortunately relied primarily on anecdotal evidence, claims that lack any scientific basis, and fallacious arguments, even resorting at some points to ad hominem, red herrings, etcetera.




> Lucky me we are thousandth kilometre from each other, otherwise you would all beat me up in the schoolyard


I think you will find that the vast majority of OptiBoarders are very open-minded and respectful of other members. Besides, we have members in most countries, so you really aren't safe either way. ;)

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## Laurie

Hello Again,

Darryl has an excellent reputation here, and in the optical community at large...I had the pleasure of meeting him years ago when he was still a very young Meister Rama! (sorry Darryl, I couldn't resist) ; )

Back to point:

Do these measurements matter? We have debated this for several pages, I would summize:

Since the learning curve is large to get everyone on board to feel comfortable talking to patients/clients and taking accurate additional measurements, it is best to use defaults until ready.

Those who are ready, go for it! As Barry has mentioned several times, he is getting fantastic results. As Darryl mentioned, the 'target' will be closer than it would with global defaults.

We are really splitting hairs here, tiny percentages of Diopter changes, however, I still believe that there are hyper-sensitive visual people who can tell the difference. I also still believe that the 1/8th Diopter ANSI tolerance is more about previous limitations in surfacing manufacture than the actual tolerance of our visual system.

: )

Laurie

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## Barry Santini

> I also still believe that the 1/8th Diopter ANSI tolerance is more about previous limitations in surfacing manufacture than the actual tolerance of our visual system.
> 
> Laurie


 
Here, I would respectfully disagree.  The only reasons why some feel that 1/8th D is too large a tolerance is that 

THE RX YOU BEGIN WITH IS NOT OPTIMIZED FOR THAT CLIENT'S VISUAL EXPECTATIONS.

This is part of my ABOM paper.  It's close to my heart.

In the end, ECPS are well advised to take those POW meaurements on EACH AND EVERY CLIENT, regardless of lenses being made.

All these "measurements" are, in reality, "contact points" between the patient and the ECP.  If nothing else, they will convey to the client that something new & special is being done now.

Something no "online" fulfiller could ever hope to duplicate.

The wise amongst us will see my point.

Barry

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## AWTECH

> Hello Again,
> 
> Darryl has an excellent reputation here, and in the optical community at large...I had the pleasure of meeting him years ago when he was still a very young Meister Rama! (sorry Darryl, I couldn't resist) ; )
> 
> Back to point:
> 
> Do these measurements matter? We have debated this for several pages, I would summize:
> 
> Since the learning curve is large to get everyone on board to feel comfortable talking to patients/clients and taking accurate additional measurements, it is best to use defaults until ready.
> ...


I agree with this as those who have a single store and a strong well trained optician can really make sure the staff is trained and up to speed. A 6 office group on the other had will probably not have the dedicated training staff to oversee this to make sure accurate measurements are actually taken by all.

The other factor in the difference between actual correct individualized patient measurements and estimates is the accuracy of the prescription.

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## Barry Santini

> I agree with this as those who have a single store and a strong well trained optician can really make sure the staff is trained and up to speed. A 6 office group on the other had will probably not have the dedicated training staff to oversee this to make sure accurate measurements are actually taken by all.


This then, is my main bone with the schools and the state of opticianry skill/education today.

2 years is not enough.  Certainly not enough to expose the students to what they need to know.

And definitely not enough to ensure competant mastery of the necessary skills to be a qualified and certified ophthalmic dispenser.

Barry

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## AWTECH

> This then, is my main bone with the schools and the state of opticianry skill/education today.
> 
> 2 years is not enough. Certainly not enough to expose the students to what they need to know.
> 
> And definitely not enough to ensure competant mastery of the necessary skills to be a qualified and certified ophthalmic dispenser.
> 
> Barry


This is a challenge for suppliers such as my company.  One state has strong state requirements and others .... Well the optician my have had a job yesterday where they had to know, "would you like fries with that?"

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## Uilleann

I believe that if each of us were to take a random sampling of our state, or even our local area - to include ALL types of dispensaries and optical practices, private, and big box etc...that we would be frightened to learn of the ability or perhaps the INability of our profession as a whole to get so much as a reliable seg ht. or accurate mono pd on a patient.

It's often pointed out that most of the populous of Optiboard are not your garden variety optician/dispenser.  Rather most here are in the upper most percentile of their trade.  And yet even here, we can't agree on what makes good sense in regards to POW measurements and lens optimization.  I think there's a good chance we'll get there, but as Barry is quick to point out, it will require much more stringent educational and practical training requirements to be put into effect industry-wide.

As things stand now, I don't see that as a realistic eventuality in the near future.  If only Arthur C. Clarke had gotten it right and made 2010 about the state of opticianry and not about big Jovian monoliths...we might be some where.  Time to find my monkey suit...now where's my bone to toss in the air?!  ;)

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## Barry Santini

> ...we would be frightened to learn of the ability or perhaps the INability of our profession as a whole to get so much as a reliable seg ht. or accurate mono pd on a patient.;)


I realy think that words like accurate or reliable are inappropriate for the skills of obtaining measurements.

I prefer "appropriate".  For instance, taking a pupil height for any type of ;lens should be relatively reasy tpo master.

Knowing what to do with the pupil height, i.e., compensating the height based upon posture, fit or intented use is *really* the skill.

My 2 cents

Barry

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## Uilleann

> I realy think that words like accurate or reliable are inappropriate for the skills of obtaining measurements.
> 
> I prefer "appropriate".  For instance, taking a pupil height for any type of ;lens should be _relatively reasy_ tpo master.
> 
> Knowing what to do with the pupil height, i.e., compensating the height based upon posture, fit or intented use is *really* the skill.
> 
> My 2 cents
> 
> Barry


*Cleaning coffee from my screen*  I thought for a second there Barry, that you'd reverted into Scooby Doo speak there.  hehehe  A good laugh, when my brain ain't yet firing on all cylinders yet this morning!  :bbg:

I get what you're saying here, though I'd still likely use my original jargon.  My point being that there are still far far too many remakes I'm aware of for things like a bad seg or pd, and that adding the complexity of POW measurements would almost certainly compound that given our current state of "training" in the industry as a whole.

Again, the simple fact that we're even here, discussing POW and it's implications, sets us apart from the vast and wide majority.  Something I'd love to see change.  Then again...wouldn't we all right?

Cheers my friend!  :cheers::cheers::cheers:

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## Barry Santini

Typiong wilh neber ve ny forte.

B

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## qsquaretoo

I guess the design optimization can tolerate the daily wearing position change in real life. So Mike's way of using "pre-set" values works. Otherwise, wearing an individualized PAL is not a man's job :) 

BTW, I read US6,089,713 and it does not teach how the parameters of wearing position are used in design optimization :), except mentioning.

-QQ

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## Optoanomalicious

Hey Mike,

Let me have a comment with regards to your little secrets.  When you start using free form lenses and the lens manufacturers ask you to measure VD, PT, and BC, these datas are relevant in order to maximise the lens' comfort for the wearer.  Now it comes down to the personnel's skill in taking these measurements whether they could be as accurate or not.  Also it depends on the quality of the lens, that's why you need to choose your lens carefully.  One is more superior than the other in terms of design.  My shop dispense mostly high index rodenstock impression and believe me, they are different..  When these datas are measured correctly and your optician is highly trained to fit the specs, That's when we're talking about price differences between Essilor Physio 360 and Rodenstock Impression.  In terms of comfort, only the individual could tell when they have it on for as long as they feel wearing them.  When you know how to do it correctly, then it should produce the optimum result my friend.  Hope this helps

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