# Optical Forums > Progressive Lens Discussion Forum >  POW compensation for digital progressives a la Zeiss Individual

## rdcoach5

Zeiss Individual asks for POW measurements for each patient. Why cannot I specify POW for any digitally  surfaced progressive, like Autograph 2 , to compensate for a frame that cannot be properly pantoscoped? Darryl?

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## Robert Martellaro

> Zeiss Individual asks for POW measurements for each patient. Why cannot I specify POW for any digitally surfaced progressive,


It depends if the software is capable, and whether that capabilty is implemented (read "paid for"). Keep in mind that free-form generators are capable creating complex surfaces as well as simple surfaces, that may or may not be optimized. Caveat emptor. 




> ...like Autograph 2 , to compensate for a frame that cannot be properly pantoscoped?


You can for the Auto 2 PAL, but not the SV lens, at least not yet.

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## Barry Santini

> , to compensate for a frame that cannot be properly pantoscoped? Darryl?


Proper "pantoscopy" requires an appropriate measurement.  But, the jury is still out as to just how this measurement is to obtain reliably obtained, independant of and without co-mingling it with client head posture.

FWIW

Barry

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## Darryl Meister

> Why cannot I specify POW for any digitally surfaced progressive, like Autograph 2 , to compensate for a frame that cannot be properly pantoscoped? Darryl


Robert summed it up nicely. Not all free-form lens suppliers actually optically optimize their progressive lenses based upon the wearer's specific prescription and/or position of wear. This is why it is important to fully understand the features of a given product.




> But, the jury is still out as to just how this measurement is to obtain reliably obtained, independant of and without co-mingling it with client head posture.


For CZV products, at least, there really is no ambiguity in _defining_ the pantoscopic angle: It is the vertical angle that the frame plane makes from a plane orthogonal (perpendicular) to the line of sight at the fitting point of the lens. When _measuring_ the pantoscopic angle, since there is no easy way to "visualize" a plane perpendicular to the line of sight without special equipment, it is typically measured from a vertical plane, which means that the line of sight should be relatively level (i.e., looking "straight ahead").

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## drk

Help me out, here.

I've seen reference on a few threads, here, to the patients head angle as a variable in pantoscopic tilt. 

I'm under the converse impression that the REASON for pantoscopic tilt is so the patient's head angle DOESN'T MATTER in it's relationship to the lens.

Which is wrong?

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## Darryl Meister

> I've seen reference on a few threads, here, to the patients head angle as a variable in pantoscopic tilt... I'm under the converse impression that the REASON for pantoscopic tilt is so the patient's head angle DOESN'T MATTER in it's relationship to the lens


Having participated in some of those discussions, myself, I can certainly understand your confusion. Some of the information presented in one or two of those threads was ambiguous; some of it was completely inaccurate.

Unless the frame is placed on the face in a different position, the relationship between the position of the eyeball and the frame + lens plane does not change. Hence, the angle between the lens plane and the line of sight, once the line of sight passes through the fitting point of the lens, does not change with head movement either. This is essentially the angle the lens makes with the line of sight in "primary gaze."

Of course, as the line of sight moves across the lens it forms a different angle with the lens plane. Lens designs properly optimized for the wearer's position of wear have the optics of the lens calculated at each new viewing angle, assuming that the lens is in a fixed position with respect to the position of the eyeball. (Technically, the effective center of rotation of the eyeball may change slightly with certain eye movements, but this effect is generally ignored in lens design.)

However, for any given wearer, the relationship between the frame + lens combination and the position of the eyeball may differ significantly. Even wearers in the same frame style can expect their lenses to rest differently relative to the eyes when worn, depending upon their particular facial anatomy. So the pantoscopic tilt angle of the frame + lens combination is indeed an important variable for optical optimization of the lens design.

That said, head posture _can_ influence how pantoscopic angle is _measured_. Since the angle of the lens must be measured with respect to the line of sight in primary gaze, which should also intersect the fitting point of the lens when corrected positioned, any unwanted vertical head tip can throw off this measurement. Of course, it will throw off the fitting height measurement as well. Much of the discussion that you are referring to may have occurred in the context of _measuring_ pantoscopic tilt accurately.

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## OCP

> Help me out, here.
> 
> I've seen reference on a few threads, here, to the patients head angle as a variable in pantoscopic tilt. 
> 
> I'm under the converse impression that the REASON for pantoscopic tilt is so the patient's head angle DOESN'T MATTER in it's relationship to the lens.
> 
> Which is wrong?


Hi drk

Pantoscopic tilt DOES matter. The issue is to measure this value prober, and in my oppinion this value can never be fixed to a specific client.


Mike

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## Barry Santini

> Hi drk
> 
> Pantoscopic tilt DOES matter. The issue is to measure this value prober, and in my oppinion this value can never be fixed to a specific client.
> 
> 
> Mike


Mike, Care to clarify what you mean by "this value can never be fixed to a specific client"

Barry

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## OCP

> Mike, Care to clarify what you mean by "this value can never be fixed to a specific client"
> 
> Barry


Hi Barry.

Regarding our previous discussion, I still think the Pantoscopic angle is not an fixet value, and therefor nearly impossible to measure. It can only be an average value.

As you know, this is my personally point of view, and will for sure get someone up in the red zone :bbg:

Mike

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## Barry Santini

Since eyewear is impossible to fix in place with respect to its fitting and adjustment, I'd have to agree with you. If you meant something else, by all means please go to the *red* zone!

Barry

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## Darryl Meister

> Regarding our previous discussion, I still think the Pantoscopic angle is not an fixet value, and therefor nearly impossible to measure. It can only be an average value.


As I said, some of the information presented in the other threads was completely inaccurate. Rather than rehash the entire discussion appearing in those threads, however, I will simply defer to another thread ostensibly dedicated to the subject of confusing eyecare professionals on the subject of free-form technology: http://www.optiboard.com/forums/show...w-this-secrets.

Some technical concepts seem to be misapplied or at least applied ambiguously in your post above, even as these concepts have been implemented with your own product (Shamir Autograph):

1. If a measurement value varies upon taking repeated measurements of the _same_ person, it is reasonable to take an _average_ of those _individual measurements_. You can certainly do this right now for any free-form lens with customization for the position of wear, including Zeiss Individual. For that matter, you could do this for _any_ measurement for _any_ lens, including the fitting height of traditional progressive lenses.

2. If only a single measurement value can be utilized for _every_ person, it is reasonable to use a representative value based upon the _average_ of the _entire population_ of potential wearers. For instance, if you order GT2 3D lenses by Zeiss, or do not supply specific position of wear measurements with Zeiss Individual, such "representative" or "default" values are used, instead. This is actually the concept that you are referring to, which has nothing to do with the first concept.




> Since eyewear is impossible to fix in place with respect to its fitting and adjustment,


I don't necessarily agree that it is "impossible" to keep eyewear relatively stable through proper adjustment, at least within a reason, but we were actually discussing the _apparent_ shift of eyewear _with head movement_ in the earlier post. For instance, if you measure the pantoscopic tilt of the frame from a vertical plane, this angle will change as the wearer tips his or chin. However, the lens, itself, generally does not change with respect to the eyeball.

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## OCP

> As I said, some of the information presented in the other threads was completely inaccurate. Rather than rehash the entire discussion appearing in those threads, however, I will simply defer to another thread ostensibly dedicated to the subject of confusing eyecare professionals on the subject of free-form technology: http://www.optiboard.com/forums/show...w-this-secrets.
> 
> Some technical concepts seem to be misapplied or at least applied ambiguously in your post above, even as these concepts have been implemented with your own product (Shamir Autograph):
> 
> 1. If a measurement value varies upon taking repeated measurements of the _same_ person, it is reasonable to take an _average_ of those _individual measurements_. You can certainly do this right now for any free-form lens with customization for the position of wear, including Zeiss Individual. For that matter, you could do this for _any_ measurement for _any_ lens, including the fitting height of traditional progressive lenses.
> 
> 2. If only a single measurement value can be utilized for _every_ person, it is reasonable to use a representative value based upon the _average_ of the _entire population_ of potential wearers. For instance, if you order GT2 3D lenses by Zeiss, or do not supply specific position of wear measurements with Zeiss Individual, such "representative" or "default" values are used, instead. This is actually the concept that you are referring to, which has nothing to do with the first concept.
> 
> 
> I don't necessarily agree that it is "impossible" to keep eyewear relatively stable through proper adjustment, at least within a reason, but we were actually discussing the _apparent_ shift of eyewear _with head movement_ in the earlier post. For instance, if you measure the pantoscopic tilt of the frame from a vertical plane, this angle will change as the wearer tips his or chin. However, the lens, itself, generally does not change with respect to the eyeball.


Darryl, nice to see you have finally learned that the Panto is only an average measure. Just as I have said many times.
Now you only need to learn a little about Vertex as well. As I have already claimed, it is impossible to measure Vertex prober as well, and does not influence the optical design noticeable.

SO all in all Panto and Vertex is somehow marketing gimmicks.  :Nerd: 

I do not say Individual and GT2 is same same if you use default measures, because I agree that Individual is a much better lens than GT2, just as Auto II is a better lens than Auto Plus. BUT that is not because of the Panto & Vertex, thats because of two complete different designs.!

But one thing your right about. We dont need to discuss that in this thread.

Mike

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## Darryl Meister

> Darryl, nice to see you have finally learned that the Panto is only an average measure. Just as I have said many times.. SO all in all Panto and Vertex is somehow marketing gimmicks... We dont need to discuss that in this thread.


I'm afraid we'll just have to agree to disagree, Mike. I believe that I explained these principles to you very clearly in the other thread, ad nauseam, so I don't really have anything more to add regarding your opinion about your Shamir Autograph product.

You obviously believe that position of wear measurements are pointless (well, all of them with the exception of wrap angle, since you currently use that one for some reason), and have chosen not to offer your customers this particular Prescriptor option with the Shamir Autograph lenses you supply.

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## OCP

> I'm afraid we'll just have to agree to disagree, Mike. I believe that I explained these principles to you very clearly in the other thread, ad nauseam, so I don't really have anything more to add regarding your opinion about your Shamir Autograph product.
> 
> You obviously believe that position of wear measurements are pointless (well, all of them with the exception of wrap angle, since you currently use that one for some reason), and have chosen not to offer your customers this particular Prescriptor option with the Shamir Autograph lenses you supply.


Your right. I think Vertex and Panto are pointless, unless you could measure the average value prober enough, but you can´t, I can´t and no one can´t. Only laser equipment mounted on the head in a week could give you a usable average. And for what reason? NONE because the pow-, and design comp. would be minimal anyway.

Mike

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## Darryl Meister

> Only laser equipment mounted on the head in a week...


While I find the notion of becoming a "cyborg" intriguing, I would recommend instead using one of the digital centration systems specifically designed for capturing these measurements, such as the i.Terminal, or using one of the inexpensive manual fitting tools that are also available.
;)




> unless you could measure the average value prober enough


Mike, as you know, I routinely disagree with most of what you post on this subject, since it is more often than not wild conjecture with no technical substantiation or clinical validation that serves only to support your own product positioning. But, in this particular instance, I think that you are still simply commingling the two very distinct concepts that I described above.

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## OCP

> While I find the notion of becoming a "cyborg" intriguing, I would recommend instead using one of the digital centration systems specifically designed for capturing these measurements, such as the i.Terminal, or using one of the inexpensive manual fitting tools that are also available.
> ;)
> 
> 
> Mike, as you know, I routinely disagree with most of what you post on this subject, since it is more often than not wild conjecture with no technical substantiation or clinical validation that serves only to support your own product positioning. But, in this particular instance, I think that you are still simply commingling the two very distinct concepts that I described above.


Hi Darryl.
First of all I´m not market our own product with these personally claims, because we need the measurement to Auto II just as anyone other "individual" product.
I fully understand your point #2, but cant see what you think I don´t understand with this. I told you that Individual *IS* actually more individual comparing to GT2 especially because of the panoramic angle.
But you know, because I know, that GT2 design is not even close to the Individual design. It´s a complete different design comparing with Individual. AND thats the MAIN reason for the better Individual design. Not the panoramic, not the Vertex but the improved design. As manfacturer of lenses, we will always use our best design for the most expensive, right? With Freeform technology we can change the design as we like to, and put in into different price levels as we change the size of the vision area, and the sharpness. This is not magic as you like us to think.

Mike

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## Darryl Meister

> I fully understand your point #2, but cant see what you think I don´t understand with this. I told you that Individual *IS* actually more individual comparing to GT2 especially because of the panoramic angle


Case in point, my points dealt strictly with the notion of "average pantoscopic tilt," irrespective of any particular product, yet you are now off on an unrelated tangent comparing the performance of GT2 and Individual.




> But you know, because I know, that GT2 design is not even close to the Individual design. It´s a complete different design comparing with Individual. AND thats the MAIN reason for the better Individual design.


I'm not really sure whether you are referring to GT2, which is a semi-finished lens, or to GT2 3D, which is a free-form lens. In any case, both are based upon the lens design platform used to design Individual, although there are subtle optical differences between the three lens designs (e.g., GT2 has more near zone emphasis, GT2 3D is a softer design overall to improve binocularity).




> This is not magic as you like us to think


Remember that I was the one supporting my arguments with scientific reasoning and actual optical comparisons. You were, and still are, the one supporting your arguments with little more than your personal assurances. I don't believe in magic, which is why I routinely encourage eyecare professionals to look beyond the "smoke and mirrors" of poorly supported marketing puffery to understand, instead, the actual implementation details of the lens design.

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## OCP

Hmmm I thought it was night or VERY early morning in Kansas? Are you sitting in Europe?
About "Scientific reasons" thats okay, but Science alone is not the answer of right and wrong. It´s only a tool.
You can make all the science about cars, but you still have the slowest car. 

Mike

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## Darryl Meister

> Hmmm I thought it was night or VERY early morning in Kansas?


It's very late, but I'm currently discussing a project with my German colleagues in Aalen.




> About "Scientific reasons" thats okay, but Science alone is not the answer of right and wrong. It´s only a tool.


I don't disagree with you. Clinical validation is very important. And you will see some very impressive clinical validation for Zeiss Individual very soon.

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## Mr. Finney

Good grief, here we go again!  Still, I can't help but interject:




> Regarding our previous discussion, I still think the Pantoscopic angle is not an fixet value, and therefor nearly impossible to measure. It can only be an average value.


Obviously, Mike wears those cool, continuously-panto-adjusting glasses, probably with mirrored lenses, that way, people of different heights can't see his eyes and it always appears as though he is looking in their direction!




> Since eyewear is impossible to fix in place with respect to its fitting and adjustment, I'd have to agree with you. If you meant something else, by all means please go to the *red* zone!
> 
> Barry


C'mon Barry, surely you would agree that if you have properly fit someone's eyewear, it will remain in pretty much the same location on their face from one second to the next??




> Darryl, nice to see you have finally learned that the Panto is only an average measure. Just as I have said many times.


Mike, maybe you need a new refraction, as that is not what Darryl said at all.  He explained it very well here, not that I would expect you to agree or understand:_

"Having participated in some of those discussions, myself, I can certainly understand your confusion. Some of the information presented in one or two of those threads was ambiguous; some of it was completely inaccurate.

Unless the frame is placed on the face in a different position, the relationship between the position of the eyeball and the frame + lens plane does not change. Hence, the angle between the lens plane and the line of sight, once the line of sight passes through the fitting point of the lens, does not change with head movement either. This is essentially the angle the lens makes with the line of sight in "primary gaze."

Of course, as the line of sight moves across the lens it forms a different angle with the lens plane. Lens designs properly optimized for the wearer's position of wear have the optics of the lens calculated at each new viewing angle, assuming that the lens is in a fixed position with respect to the position of the eyeball. (Technically, the effective center of rotation of the eyeball may change slightly with certain eye movements, but this effect is generally ignored in lens design.)

However, for any given wearer, the relationship between the frame + lens combination and the position of the eyeball may differ significantly. Even wearers in the same frame style can expect their lenses to rest differently relative to the eyes when worn, depending upon their particular facial anatomy. So the pantoscopic tilt angle of the frame + lens combination is indeed an important variable for optical optimization of the lens design.

That said, head posture_ _can influence how pantoscopic angle is_ _measured. Since the angle of the lens must be measured with respect to the line of sight in primary gaze, which should also intersect the fitting point of the lens when corrected positioned, any unwanted vertical head tip can throw off this measurement. Of course, it will throw off the fitting height measurement as well. Much of the discussion that you are referring to may have occurred in the context of_ _measuring pantoscopic tilt accurately."_




> Now you only need to learn a little about Vertex as well. As I have already claimed, it is impossible to measure Vertex prober as well, and does not influence the optical design noticeable.


I really doubt you have the credentials to say what Darryl needs to learn; might want to take a little of your own advice there.




> SO all in all Panto and Vertex is somehow marketing gimmicks.


Ridiculous.  Are you serious?  I sure hope not.  Probably so though.

Now don't get me wrong here people, I'm not pretending to be the smartest optician on the planet, but seriously, this Mike guy has his own agenda.  Not only does he try to make us all think that his product is the only one worth having, but he also likes to belittle people and talk down to them when they say there may be other options or answers.  It's pretty obvious that Darryl knows his stuff; the jury's still out on Mike.  We all know that vertex and panto can and do make a difference in vision.  Well, all of us except Mike, that is.

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## mahmoud.hamza

From my point Of view 
I agree that The panto and the vertex can never be exact 100% but is better to have one near value then nothing that is why i think that the vertex and the panto can not be marketing issue to sell more!!
also the calculation software that are in the market and that calculate the PAL surface prouve that the panto and the vertex can change a lot the power espacelly for a panto more then 10°
regards

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## OCP

Okay finney.

Obvious you are wery low educated here among others. Without sounding lecturing, I will ones again explain for you, and king Salamon, why Panto is a gimmick measure and Panoramic is not.
We all know that by increasing the Panto angle a little more we can sometimes solve a reading issue, but this is only because some frames are adjusted more vertical on the nose than others.  It can happens even though you have customized a pair of  Zeiss Individual, Impression, Auto II and even though you have measured the Pantoscopic tilt prober. If the Pantoscopic tilt are 0-5 degrees some gets reading problems you can solve by increasing the angle!

I and other well educated and informed opticians, know that most people, cant feel any different at all when changing the Pantoscopic tilt between 5 and 15 degrees.! 
You and others obvious dont know why. I tell you. Because the tilt from 5-15 degrees don´t make any noticeable changing in the design, and the small changings only affect a very small area of the lens, and thats the small reading area.

Otherwise the Panoramic angle. THAT´s a different story. When you change the panoramic angle just 5 degrees it immediately change the comfort of the lens. You get horrisontal prism effect both in the distance and in the reading zone, and destroy the size of the reading area every time you increase the pantoscopic angle with just 3 degrees. Darryl, you and others should be careful with claiming that I´m wrong when you don´t know a s*** about this. Someone here are very low educated in optics or just students that believe in all Mr. Meister tell you. Are there any well educated opticians left in this forum at all?????

You are bullying the wrong person here finney and please tell me what you think my agenda is? I don´t see your point.

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## Darryl Meister

> Panto is a gimmick measure and Panoramic is not... Because the tilt from 5-15 degrees don´t make any noticeable changing in the design, and the small changings only affect a very small area of the lens, and thats the small reading area.


First of all, I want to reiterate that _both_ measurements are important. While I still find it odd, and more than a little self-serving for your product, that you believe one position of wear angle is "very important" while the other is a "gimmick," I am willing to entertain your reasoning one last time.

Secondly, there is no _optical_ difference between pantoscopic and face-form (panoramic) tilt. Each introduces the exact same optical effect, oblique astigmatism, albeit with a different cylinder axis. And each interacts with the optics of the lens design in similar ways. I already posted contour plots for you to look at showing the effects of this tilt, which you essentially ignored since they disproved all of your wild conjecture, in the other thread that you're attempting to rehash here.




> If the Pantoscopic tilt are 0-5 degrees some gets reading problems you can solve by increasing the angle! You get horrisontal prism effect both in the distance and in the reading zone... When you change the panoramic angle just 5 degrees it immediately change the comfort of the lens.


What you're describing is not an optical phenomenon. You're simply increasing the field of view through the near zone by bringing it closer to the eye. Or reducing the field of view through one axis or the other by tilting the lens about an axis perpendicular to it. And either pantoscopic tilt (vertical compression) or face-form tilt (horizontal compression) will reduce the field of view.

Further, this kind of non-optical reduction in field of view due to lens tilt is actually quite negligible for 5 deg of face-form tilt. But, since I like to stick to facts and not conjecture, I will "do the math" for you since you continue to refuse to do it yourself, assuming a near zone size of 20 mm made on a 6.00 Base hard resin (1.500) puck with a 5 mm center thickness:

_Apparent Width = Actual Width * COS Tilt_
_Apparent Width = 20.0 * COS 5_
_Apparent Width = 19.92 mm_

And, for the induced prism that you mentioned:

_Induced Prism = Center / Index * Base * 100 * TAN Tilt_
_Induced Prism = 0.005 / 1.5 * 6.00 * 100 * TAN 5_
_Induced Prism = 0.17 Prism Diopters_

So, ignoring the optical effects of oblique astigmatism for now, which you have no interest in for some reason, you are looking at a reduction in near viewing zone with of less than 0.1 mm and induced horizontal prism of 0.17 PD with 5 deg of face-form tilt. And these two effects are solely responsible for the major "discomfort" for wearers that you describe above as well as for the general dissatisfaction that wearers may express for a given pair of progressive lenses?

Then I guess it's a good thing that we optimize the Individual lens design for face-form tilt, in addition to eveything else.




> Darryl, you and others should be careful with claiming that I´m wrong when you don´t know a s*** about this.


After fifteen years, that's probably the single silliest thing that I have ever read on OptiBoard. And I say that with the lens designer's version of CZV's free-form optical design engine literally running on my computer in the background.




> You are bullying the wrong person here finney and please tell me what you think my agenda is?


Mike, you made your agenda very clear in your other threads. Further, I'm not bullying you. Nor do I engage in childish insults and ad hominem. In fact, I would prefer not to get into these protracted debates with you, since you typically resort to insults in the absence of any scientific reasoning or clinical evidence to support your arguments.

In any event, as the title indicates, this thread about position of wear customization in Zeiss Individual and similar products. Since you are obviously not sufficiently familiar with the technical details of the position of wear customization of Zeiss Individual, your posts in this thread serve only to attempt to derail legitimate discussion of a competitor's product with wild speculation. You have already started similar threads on this topic, like *this thread*, ostensibly for the sake of promoting your own product, and I'm sure that your input in those threads would be much more appropriate.

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## OCP

You still mix up design and power compensating.
I did never say Panto is irrelevant.
I did never say panto does not influence the power comp.
-but I did say some here are very low educated in optics.

This is ridicules as long you think Zeiss individual and Zeiss Infral is the answer of all the needs and all optical issues. Your so wrong.

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## Darryl Meister

> You still mix up design and power compensating.


Do you remember me attempting to explain to you in great detail the differences between compensating for lens power and optimizing the lens design for the position of wear in your other thread? In particular: *Here* and *Here*.




> I did never say Panto is irrelevant.


You've actually been contradicting yourself on this topic to suit your needs. In this thread, alone, you've stated:

_"Pantoscopic tilt DOES matter. The issue is to measure this value prober, "_
_"I will ones again explain for you, and king Salamon, why Panto is a gimmick"_
_"most people, cant feel any different at all when changing the Pantoscopic tilt"_
_"I think Vertex and Panto are pointless"_

You originally argued that pantoscopic tilt is important, but because it is constantly "changing on the face" somehow, impossible to measure. Once other participants expressed disagreement with this notion, however, you simply started arguing that pantoscopic tilt is instead "pointless" because it has no optical effect on the wearer.




> This is ridicules as long you think Zeiss individual and Zeiss Infral is the answer of all the needs and all optical issues


I _don't_ think that Zeiss Individual is the answer to all optical issues. Nor do I think that Shamir Autograph is.




> Your so wrong


Yes, you've made your opinion clear. Unfortunately, you continue to do a poor job of supporting that opinion.

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## OCP

You sound more and more like one that are selling expensive equipment to take all the worlds unimportant measures.
Let me refresh your memory to use the right contributions from me.

I said from the beginning that Pantoscopic was not a fixed value and nearly impossible to measure prober, so I suggest to use ex. three standard measures like 5-10-15 and consider this visual. Everyone called me an idiot and try in different ways to explain me, that this was for sure an fixed value. Now we know that Pantoscopic is an average, and therefor not an fixed value (Still everyone call me an idiot and thats okay with me. hahahaha).

I said that Vertex was impossible to measure prober, because no one here can do it correct and the power only change minor below 5D. One simple issue is, how do you mount the lens in the frame? That can easily change the vertex 3 mm. You claim that ½ mm vertex was so, and so important. How can can you claim such a ridicules thing?

I know your selling a very expensive Infral to take unimportant measures, but telling lies in this forum and get respect and honour for this................. I could vomit. (sorry my Frensh).

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## Darryl Meister

> You sound more and more like one that are selling expensive equipment to take all the worlds unimportant measures.


I do not use OptiBoard as a promotional vehicle for my company's goods or services. Nor do I condone such behavior by others, which is why I often take issue with many of your posts.

As for "selling expensive equipment," Carl Zeiss Vision makes a free tool available to eyecare professionals to take position of wear measurements. As does Shamir.




> Everyone called me an idiot


Despite your inveitable insults, and the fact that you deliberately ignore every point anyone ever makes in these threads, _I_ certainly haven't called you an idiot.




> Now we know that Pantoscopic is an average, and therefor not an fixed value (Still everyone call me an idiot and thats okay with me. hahahaha).


I see that once again you have ignored everything in these posts.




> the power only change minor below 5D.


And you are once again confusing power compensation with optical optimization.




> I know your selling a very expensive Infral to take unimportant measures


Actually, _you_ are the only one who has mentioned the Infral system.




> , but telling lies in this forum and get respect and honour for this................. I could vomit.


The truly scary part is, you're probably serious.

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## mahmoud.hamza

We are not in a ware

try to be more objective and I am sûre that you and all others will well understand every thing 

can some one give us a real definition Of the "power compensation " and the optical optimization"
from that we can fix a subject  and reach the target :)

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## NewTop

Sorry Mike, I have to agree with Darryl here.  

"power compensation" is the differance in power between vertex distance at refraction and vertex distance with the frame. In contacts this is very important, a refraction of -3.00 at 12mm gives a (soft)contact of -2.75.

"the optical optimization" keeping it very basic, if the vertex distance with the frame is larger you need a softer design or more a-spherical in single vision.

Vertex distance at refraction, everage aprox 12 mm and can be easily measured at any phoropter.
Vertex distance with the frame, not very easy to measure and a bit variable.

Mike has a point when he says that not everone can measure vertex and and tilt properly.

Regards,

John (allso a reseller of Shamir in Europe)

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## OCP

Hi Newtop.
Nice to hear from you.

If you measure the refracted Vertex to 14 and the fitted Vertex to 12 in 3D you will maximum get a difference of aprox. 0.01D so absolutely nothing noticeable difference.
When you say everyone can easily measure the Vertex in a phoropthor your wrong. It´s so impossible that 3 people would get different measures, and to measure the Vertex in a frame with out knowing anything about how the lens will be mounted in the frame is just as precise as guessing on the lottery number.
It´s all about average values and guesswork.

Your right about the optical optimazation and how we can use the Pantoscopic and the Vertex values. I dont disagree, but if we cant measure these NON fixed values prober anyway you can just as well using standard values.

The US boys here have no problem measure Panto and Vertex, because in the US these values are 100 % fixed and very easy to measure. In Europe it´s not. WHY? Are we so different in Europe, or are the Americans really so special??

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## NewTop

> If you measure the refracted Vertex to 14 and the fitted Vertex to 12 in 3D you will maximum get a difference of aprox. 0.01D so absolutely nothing noticeable difference.


Correct, thats power compensation. If you talk about optical compensation you're not correct. A vertex in the frame of 14 gives you a softer FreeFrame lens than a vertex in the frame of 12 in the same power.




> When you say everyone can easily measure the Vertex in a phoropthor your wrong.


No I'm not, have you seen the vertex measurement prisms on the temporal side of most phoropters?




> to measure the Vertex in a frame with out knowing anything about how the lens will be mounted in the frame is just as precise as guessing on the lottery number.


Your right, so if this is measured in a wrong way or mounted in the wrong way you won't get a perfect lens just a good lens. But there are opticians who know what they are doing. 





> The US boys here have no problem measure Panto and Vertex, because in the US these values are 100 % fixed and very easy to measure.


Pantoscopic tilt is just as variable as fittingheight and you measure it in the same position as you measure the fittingheight.

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## OCP

> Correct, thats power compensation. If you talk about optical compensation you're not correct. A vertex of 14 gives you a softer FreeFrame lens than a vertex of 12 in the same power.
> 
> 
> 
> No I'm not, have you seen the vertex measurement prisms on the temporal side of most phoropters?
> 
> 
> 
> Your right, so if this is measured in a wrong way or mounted in the wrong way you won't get a perfect lens just a good lens. But there are opticians who know what they are doing. 
> ...


My biggest problem here on this forum is to explain my self prober enough. If I could only explain in danish it would be much more easy.

To build an individual lens 100 % perfect, I think this is what we want to everyone, we need 100 % accurate measures, right?
We dont want any source of errors.
We can only measure the Pantoscopic tilt right here and right now, without taking the clients real life head position in consiteration.
We can only measure the refracted and the fitted vertex right here and now, without taking the mounting of the lens in the frame in consiteration.
I know all this very well and we cant disagree about this.

BUT what will you win in the end of the day, if these values only give a minor effect anyway, and so many source of errors?
You can win a little bit of design compensating (if you measure 100% correct) and a little bit of power compensating if you measure 100 % correct.
BUT what if you ½ the times measure a little bit incorrect? All in all it´s not a question about taking these  irrelevant measures.

We have made a very small investigation with a few clients in Denmark.
We put them in similar powers with Autograph II with hypothetical Panto and Vertex and with fixed Vertex and Panto. (Panto 5 degree from measured, Vertex 3 mm from measured)
So far NO one could feel any difference at all.

This strength my believe that this is more a market gimmick than this gives any noticeable improvement.

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## NewTop

> My biggest problem here on this forum is to explain my self prober enough. If I could only explain in danish it would be much more easy.


The same here but in Dutch:)




> To build an individual lens 100 % perfect, I think this is what we want to everyone, we need 100 % accurate measures, right?
> We dont want any source of errors.


If you try to aproch perfection you have to measure these difficult values. 




> We can only measure the Pantoscopic tilt right here and right now, without taking the clients real life head position in consiteration.


You can say the same thing about fitting height.




> We can only measure the refracted and the fitted vertex right here and now


We can only measure the power right here and right now. The vertex at refraction is fixed and lasts for 15 minutes. 




> without taking the mounting of the lens in the frame in consiteration.
> I know all this very well and we cant disagree about this.


Agreed




> BUT what will you win in the end of the day, if these values only give a minor effect anyway, and so many source of errors?


Source of errors?
Lets say I have a client with a very large nose, he has a frame vertex of 16mm. What would be the best choice:

A) Autograph PLUS
B) Autograph FreeFrame ( I give a frame vertex of 14, everyone can notice that the frame is a bit far away from the eyes)




> You can win a little bit of design compensating (if you measure 100% correct) and a little bit of power compensating if you measure 100 % correct.
> BUT what if you ½ the times measure a little bit incorrect? All in all it´s not a question about taking these  irrelevant measures.


The measurements are not irrelevant, its irrelevant to sell a compensated lens to an average person with an average frame. A client couldn't tell the differance from a PLUS to a FreeFrame if all the "special" values are average and the fittingheight is 14, 16 or 18.

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## Darryl Meister

> can some one give us a real definition Of the "power compensation " and the optical optimization"


NewTop touched upon the differences. I also have a few articles on the subjective available for download from the OptiBoard File directory that you might find useful, including *Progress in the Spectacle Correction of Presbyopia*, a two-part series published in Clinical & Experimental Optometry.

_Prescription compensation_ simply refers to any deliberate changes to the original prescription at the distance and near measurements points of the lens. When a lens is tilted or displaced, the prescription of the lens effectively changes. It is possible to "compensate" the original prescription for this effect when there is a significant difference between the orientation of the fitted spectacle lenses and the trial-frame or refractor-head lenses used to determine the initial correction. This commonly applied to certain free-form lenses and even to semi-finished lenses in "wrap" frames or of high power.

_Optical optimization_, on the other hand, refers to changes made to the actual _lens design_. When optimizing modern progressive lenses, the position of the fitted lens is utilized to "ray trace" the optical performance of the lens-eye system for various points over the lens. Since the position of the lens dictates the viewing angles and distances required to see through any given point on the lens, the lens position significantly influences the ray-traced power calculations and, hence, the optics of the lens design. It is therefore possible to "dial in" the wearer's specific position of wear in order to recalculate the optics of the lens design appropriately.






> Mike has a point when he says that not everone can measure vertex and and tilt properly


I agree that this angle is difficult for some eyecare professionals to measure properly, at least without sufficient training. However, that doesn't make this measurement any less important. Prior to the widespread use of manual-focusing focimeters, _lens power_ was difficult to measure as well. But few would argue against its importance.

And I agree that some wearers may replace their eyeglasses in slightly different positions on occasion, particularly if the eyeglasses have not been adjusted properly. Mike has been mistakenly associating normal changes in _head tilt_ with changes in _pantoscopic angle_, however. Pantoscopic tilt does _not_ change as the wearer raises or lowers his or her head.

John, I agree with virtually all of your comments. Although I would be genuinely surprised if the lens designers at Shamir actually supported many of Mike's statements, I think your posts reflect very positively on Shamir.




> Are we so different in Europe, or are the Americans really so special??


Actually, measuring and supplying the pantoscopic tilt angle was first pioneered in Europe ten years ago. The first-generation Individual design used this measurement when it was launched in 2000. I believe that Rodenstock also accepted certain position of wear measurements rather early on for their Multigressiv lenses.




> We have made a very small investigation with a few clients in Denmark... So far NO one could feel any difference at all


The University of California at Berkeley's Clinical Research Center conducted a randomized, double-masked study of 100 wearers comparing Zeiss Individual to traditional progressive lenses, and the study yielded a statistically significant preference for Zeiss Individual. The results will be published in a peer-reviewed journal very soon.

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## Steve Machol

> You sound more and more like one that are selling expensive equipment to take all the worlds unimportant measures.
> Let me refresh your memory to use the right contributions from me.
> 
> I said from the beginning that Pantoscopic was not a fixed value and nearly impossible to measure prober, so I suggest to use ex. three standard measures like 5-10-15 and consider this visual. Everyone called me an idiot and try in different ways to explain me, that this was for sure an fixed value. Now we know that Pantoscopic is an average, and therefor not an fixed value (Still everyone call me an idiot and thats okay with me. hahahaha).
> 
> I said that Vertex was impossible to measure prober, because no one here can do it correct and the power only change minor below 5D. One simple issue is, how do you mount the lens in the frame? That can easily change the vertex 3 mm. You claim that ½ mm vertex was so, and so important. How can can you claim such a ridicules thing?
> 
> I know your selling a very expensive Infral to take unimportant measures, but telling lies in this forum and get respect and honour for this................. I could vomit. (sorry my Frensh).


Your derogatory posts and language are simply not acceptable on  OptiBoard. If you cannot act professionally and maturely, then find  another playground to play in. This conduct will no longer be tolerated.

Everyone can personally thank OCP (hiding behind a pseudonym) for this thread being closed.

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