Progressives - Can these be made?

[GeauxTigers]

I'm a new presbyope trying progressives, and fitting has not proved successful after six attempts. I'm hoping someone here can give me some advice before I go to a new OD for a second opinion and lensometry. To (hopefully) demonstrate to you I'm not a reluctant adapter, the first three pairs were by Sears, who among other things, once undershot the seg height by 4mm, so I had only a tiny sliver to read through, and another time laterally misplaced the optical center by 10mm. Next I tried Eyemasters, who got the axis wrong by 8 degrees on one lens and overpowered the other 0.5 diopters, and the redo repeated the axis error and introduced a horrible ripple defect in the opposite lens. So, I went to another Eyemasters and spoke to an optician (recommended by my OD) who seemed to know her stuff well and was very concerned about making me a pair of glasses that work. To that end, she special-ordered a polishing tool intermediate between the two she already had to make me the best lens possible. I picked up the new glasses today, and they are indeed the best I've had so far, but I'm still seeing better out of my old SV glasses for intermediate and distance vision, and I don’t think this will improve with time. I’ve learned how to dot the lenses, so I went ahead and did that, and the PD and seg height appear dead accurate per the OLA Progressive Identifier (which after printing without scaling, I measured to ensure 1mm really is 1mm). So, let me briefly explain the defects I'm observing. These are Essilor Natural lenses, BTW, and here's my prescription:

OD: +1.00, -4.25, 015
OS: +0.25, -3.75, 162
Add: +1.50
PD: 30/29
Seg height: 20

These glasses do have face form and an appropriate amount of pantoscopic tilt.

The axis is once again wrong in the left lens. I get sharp vision when I rotate the left lens a fair amount clockwise from my perspective, or to put it another way, the temple part goes up, and the nasal part goes down. Can anyone tell me what this does to the axis, which is prescribed as 162, i.e. does it increase or decrease? (My 3 year old pair had an axis of 165 (same OD) and my 10 year old pair 167 (different OD). My current OD did measure me about a year ago as 160, but I never had those glasses made.) In addition to sharpening the focus, rotating the lens gets rid of what I’ve come to call “the slanties,” those little lines I observe descending from right to left from the bottoms of characters crawling across the bottoms of cable news channels, the text being yellow on black background.

As for the right eye, I see best when I turn my head a bit left while keeping my gaze fixed on the same spot directly in front of me. This brings the center and all four corners of my 17" computer screen into good focus for my right eye, while the axis adjustment does the trick for the left eye. Again, the PD and seg height seem to be accurate for both lenses, so it doesn't make sense to me that I see best through a spot about 3mm temple-ward from the dot on the right lens.

The optician says the lenses were made accurately, and as best I can tell, they were with respect to intended PD and seg height, but I haven't presented these findings to her yet. These defects are very familiar to me, as they've affected several previous pairs to various extents, which did not improve in the several days I tried wearing them. The OD has confirmed my findings in three out of three prior lensometries. The OD stands by the prescription, BTW, and verified it with a sort of “wearable phoroptor” (i.e. a big heavy pair of adjustable glasses I don’t know the name of).

I haven’t spoken to anyone yet about this pair. What should my next step be? I’ve been dealing with this for nearly two months, and I’m about to give up. Once again, I’m left feeling that these glasses will be great, and I’ll be able to get by with just the one pair, if only these defects can be addressed. Frustrating!

[Texas Ranger]

tiger fan, lot of stuff in your post, and don't know that I can discuss it all..but, 1, when you tilt you left lens temple up, you are increasing the axis toward you old axis of 165. many folks test a bit differently in "trial frames", since they are using 2 lenses, the sphere and the cyl, and I believe that there is some guesswork involved in the axis settings? and were they plus cylinder are minus cylinder trial lenses, I believe that makes a lot of difference in moderatley high astigmatism rxs. when you dot the reference spots and measure the pd and seg hts; it doesn't mean that they are exactly there, in reality, only that the "add power" made by the lens mfr. on the front of the lens is in the right position. the Rx is ground on the back surface in the grinding process, and in that process the axis can be off, or there could be unwanted prism that has you seeing cleaer 3mm temporally, sounds like both axes need increasing a bit. it is likely that there is prism in the lens, both lens rxs are 15 degrees off 180, so there is some natural slant. another critical factor in the near is that the add power is on the front of the lens and cylinder power on the back, in the exam, the optical center of the sphere is in line with the axis line of the cylinder, in the glasses that is still hopefully true(if prism wasn't ground), but the add power is 14-18mm BELOW that power intersect, so it is not and cannot be the same in the glasses as it was in the exam. it is quite compromised. for the best reading rx, only a SV lens will emulate the exam results precisely. Was a corneal reflection pupilometer used to measure monocular pds when you were fitted? were monocular seg heights measured? you didn't give us your old rx, that you could see fine with, but that is an important consideration, and you age is important, perhaps a 1.50 add is too much to start with? best wishes.

[GeauxTigers]

tiger fan, lot of stuff in your post, and don't know that I can discuss it all..but, 1, when you tilt you left lens temple up, you are increasing the axis toward you old axis of 165. many folks test a bit differently in "trial frames", since they are using 2 lenses, the sphere and the cyl, and I believe that there is some guesswork involved in the axis settings? and were they plus cylinder are minus cylinder trial lenses, I believe that makes a lot of difference in moderatley high astigmatism rxs. when you dot the reference spots and measure the pd and seg hts; it doesn't mean that they are exactly there, in reality, only that the "add power" made by the lens mfr. on the front of the lens is in the right position.

Didn't know that about the spots. Throughout this ordeal, everyone has been proceeding as if the spots were the last word on the subject.

the Rx is ground on the back surface in the grinding process, and in that process the axis can be off, or there could be unwanted prism that has you seeing cleaer 3mm temporally, sounds like both axes need increasing a bit. it is likely that there is prism in the lens, both lens rxs are 15 degrees off 180, so there is some natural slant. another critical factor in the near is that the add power is on the front of the lens and cylinder power on the back, in the exam, the optical center of the sphere is in line with the axis line of the cylinder, in the glasses that is still hopefully true(if prism wasn't ground), but the add power is 14-18mm BELOW that power intersect, so it is not and cannot be the same in the glasses as it was in the exam. it is quite compromised. for the best reading rx, only a SV lens will emulate the exam results precisely. Was a corneal reflection pupilometer used to measure monocular pds when you were fitted?

A pupilometer was used at Sears, but I don't know what their results were. The OD did not use one, but her measurements were confirmed at Eyemasters, again by hand, and before looking at the Rx. Once they dotted up the dummy lenses, I looked through each and verified the dot was darkest looking straight ahead.

were monocular seg heights measured? you didn't give us your old rx, that you could see fine with, but that is an important consideration, and you age is important, perhaps a 1.50 add is too much to start with? best wishes.

A few weeks ago, I asked if my pupils were level, and the OD said yes. As for my Rx, here are a couple of old ones, then the new one:

Dec 1993 (different OD than current)
OD: +0.50, -4.25, 018
OS: -0.50, -3.75, 167

Jan 2001 (same OD as current)
OD: +1.25, -4.50, 015
OS: 0.00, -3.75, 165

Sep 2004 (current OD)
OD: +1.00, -4.25, 015
OS: +0.25, -3.75, 162
Add: +1.50
PD: 30/29

I can't see squat out of the 1993 glasses, but the 2001 ones are still pretty good beyond 30" or so. FWIW, I've never had any glasses remade before this progressives ordeal, as there haven't been any problems before now. As for age, let's just say early forties. :) Concerning the add power, it was originally prescribed as +1.00 for bifocals and +1.25 for progressives. This was increased to +1.50 for one of the early remakes, and it was done at the same time the OD corrected a seg height that Sears measured too small. I was concerned about changing more than one variable at a time, and I asked about that, and the response was, "we're doing that because the frame is small." My current frames are 31mm deep and seg height is 20mm, and that's been pretty consistent from frame to frame during this process. (Of course, the seg heights were remeasured with each new frame.)

Thanks for your reply. A lot of good new information there. I guess my main question is, how can I get the OD and/or optician to apply my real world observations to the measurements they take and use to grind my lenses? During at least one of my lensometry visits, I explained I could see better through the right lens by turning my head left. The OD said she couldn't explain that, and it's a pretty common factor over several sets of glasses made by three different labs. Ditto for the left lens rotation. Again, the OD says the Rx is correct, and it's the lenses that have been at fault, but this time, at least, the dots seem to be in the right place. However, if the dots aren't the last word on the subject, what is? Is it possible for them to do lensometry, observe what I do in order to see well (i.e. rotate the left lens and look temporally through the right lens) and accurately measure the difference, and from that determine the proper parameters for making my lenses?

[Robert Martellaro]

To everyone,

I had this happen a couple months ago, +4.50 cyl, PAL, +2.00 add with vision in the left only. Her Rx axis was historically 90, but turning the lens towards 95 improved the vision. I didn't have trial lenses close enough to the Rx so I sent her back to the Dr. to check the Rx while I had the lab supply a SV round lens in her distance Rx. New Rx from Dr. was 92. I borrowed a gauge master and confirmed that the axis dial was on the money. To make this shorter she saw best at 94 or 95 so I ordered a new lens and the smile on her face said it all. Equipment error? I measured a variety of old glasses dating back to the early 90's and they were all in the 87-91 range from two different MDs, with the last one employing a tech who knows how to refract. This is not the first time I've seen this happen. I'am stumped.

To the poster,

162 is probably the wrong axis, no matter how many times the doc says it's right. Doctors aren't omnipotent, just plain old folk like you and me. If they won't work with you, find one who will and then tell all your friends and neighbors.

Hope this helps

Robert

[slaboff]

how long do you work on the computer, if the answer is more than 3 hours i would reccomend having a pair of computer glasses made with either shamir office lenses to provide a nice wide intermediate area or single vision computer only glasses... i know that you said that the pd is correct however it sounds to me that the left eye optical center is slightly out (away from you nose) as far as the axis issues go maybe you should get a second opinion on the script... the natural is not a bad lens design, however it is a very old design and you would have a much wider channel in a newer lens design such as a shamir genesis...

[GeauxTigers]

To the poster,

162 is probably the wrong axis, no matter how many times the doc says it's right. Doctors aren't omnipotent, just plain old folk like you and me. If they won't work with you, find one who will and then tell all your friends and neighbors.

Hope this helps

Robert

Hi Robert,

I'm definitely leaning towards going to a new OD for a second opinion. I agree the prescribed axis is probably wrong on the left lens, as multiple labs have got it wrong in the same way, though the OD said she measured the axis to be 154 on the last set, not 162. Concerning the right lens, the sphere has gone from +0.50 to +1.25 to +1.00 in 1993, 2001, and 2004, respectively. Is it possible it's now too weak? I'm afraid if they were to move the fitting cross temporally, it might be fine at the computer, but in the real world, I'd be back to the poor distance performance and massive swim defect I observed in an earlier pair.

Here's a little experiment I did, which I hope provides some useful information. I picked a spot in the center of my monitor to focus on from about 30", and I panned as follows. I started looking through the right lens near the nosepad and panned so I ended up looking through the temporal part. In both distance and high intermediate areas, I find that the text starts out readable but not sharp, stays about the same until I get to that sweet spot I mentioned earlier, which is about 3mm temporal to the fitting cross, where it gets sharp, then the sharpness declines, and finally ends up sharper, but not quite as sharp as in the sweet spot. It follows a pattern like this, where minus signs represent not-quite-sharp, plus signs sharp, \ signs not-quite-sharp plus a sort of soft, wide distortion, which skews the image, and * the fitting cross:

Right lens
nose -> temple
-----*--++\\++

The left lens does not do this. Its sharpness increases from nosepad area to fitting cross and pretty much maintains this sharpness out to the temporal area with no weird distortions.

[Chris Ryser]

Being a myopic case you belong to the type of poeple that are more difficult to please and satisfy, and when things do not seem right they start to investigate.

Said that, you have 2 problems, assuming your PD and power is right, you are stating that you still see better with the old single vision.

Therfore, I assume, this is the first time of you wearing distance and reading powers on the same lens. You previously just took off your glasses or slid them up your forehead.

1)

You are starting on progressive lenses at 50% of the addition scale (+1.50 add) which goes usually from +075 tp +3.00. This brings you allready into a 50% reduction of the width of the possible progressive and reading portion of the lens. You also have a larger portion of lateral distortion than if you would have started to waer this type of lenses a few years back without problems.

2)

A height of 20mm is definitely squeezing the comfort tolerance. You should habe chosen a frame that would have allowed a good 24 mm for a confortable height. But these days the fashion says go for a smaller frame and forget the technical problems it can cause. The chinese used to bend the toes of the female children upwards because it was fashion a few hundred years ago, even when later on in life they could not walk properly, but it was the fashion.

Conclusion:

I general opticians are in general selling the advantages of progressive lenses without mentioning some drawbacks on their limits. Manufactureres are publicly advertising in magazines and TV and make the public believe that their lenses are the ultimate solution. There are many more factors to be considered tha just the RX, the PD and the frame. Profession, work related vision, use of computers, outdoor activities and many more factors should be taken into consideration before choosing a pair of lenses and or a frame.

[ksquared]

Being a myopic case you belong to the type of poeple that are more difficult to please and satisfy, and when things do not seem right they start to investigate.

Would you rather we just accepted our spectables as is? Regardless? I personally would prefer to find an OD/optician who belongs to the type of people who has developed a better understanding of how to correct "myopia". We start our invetigatoin out of desperation (in most cases). If we already know we can get excellant (or at least good) vision from our specs, it's difficult to "buy" some of what we're told. But the real bottom line is what our eyes tell us. Can I see better or worse. If worse, something is not right. JMHMO -

[slaboff]

A height of 20mm is definitely squeezing the comfort tolerance.[/b] You should habe chosen a frame that would have allowed a good 24 mm for a confortable height. But these days the fashion says go for a smaller frame and forget the technical problems it can cause. The chinese used to bend the toes of the female children upwards because it was fashion a few hundred years ago, even when later on in life they could not walk properly, but it was the fashion.

Conclusion:

I general opticians are in general selling the advantages of progressive lenses without mentioning some drawbacks on their limits. Manufactureres are publicly advertising in magazines and TV and make the public believe that their lenses are the ultimate solution. There are many more factors to be considered tha just the RX, the PD and the frame. Profession, work related vision, use of computers, outdoor activities and many more factors should be taken into consideration before choosing a pair of lenses and or a frame.

I agree that you should have had a seg height of 24 with this particular lens and that progressives have some serious limitations.... the optician who fit you should have put you into a varilux panamic which only requires a 18 seg height... however there are alot of other types of progressives that the optician could have put you in that would have worked better than the natural you were fitted with... also like i said in my previous post i think you should double check the left eye fitting cross... part of the frustration of this business is when you hand someone a new pair of glasses and the patient says after wearing the glasses for not even a minute that they cannot see out of them... without giving them a try first (wearing for at least a week) also the adaption period for a first time progressive wearer is 2 weeks to adapt to the new type of lens... I am not saying that you should just accept poor vision... I am saying give it some time and then if your still having problems go back and let them know about it... if they are any kind of reputable outfit they will help you...

[GeauxTigers]

Being a myopic case you belong to the type of poeple that are more difficult to please and satisfy, and when things do not seem right they start to investigate.

Said that, you have 2 problems, assuming your PD and power is right, you are stating that you still see better with the old single vision.

Therfore, I assume, this is the first time of you wearing distance and reading powers on the same lens. You previously just took off your glasses or slid them up your forehead.

Do you really think with my Rx, that would've worked? :) And BTW, that's not quite what I said about my old SV glasses.

1)

You are starting on progressive lenses at 50% of the addition scale (+1.50 add) which goes usually from +075 tp +3.00. This brings you allready into a 50% reduction of the width of the possible progressive and reading portion of the lens. You also have a larger portion of lateral distortion than if you would have started to waer this type of lenses a few years back without problems.

2)

A height of 20mm is definitely squeezing the comfort tolerance. You should habe chosen a frame that would have allowed a good 24 mm for a confortable height. But these days the fashion says go for a smaller frame and forget the technical problems it can cause. The chinese used to bend the toes of the female children upwards because it was fashion a few hundred years ago, even when later on in life they could not walk properly, but it was the fashion.

Conclusion:

I general opticians are in general selling the advantages of progressive lenses without mentioning some drawbacks on their limits. Manufactureres are publicly advertising in magazines and TV and make the public believe that their lenses are the ultimate solution. There are many more factors to be considered tha just the RX, the PD and the frame. Profession, work related vision, use of computers, outdoor activities and many more factors should be taken into consideration before choosing a pair of lenses and or a frame.

That's all well and good. However, I don't see how it addresses the problems I described, namely:

1. Rotating my left lens makes my left eye sharp.
2. Looking through a point 3mm temporal from the fitting cross makes my right eye sharper.

This is unacceptable, and it's not something I will "adapt" to. Maybe I didn't make it clear, but the left lens axis problem affects the entire lens, including the distance part. The right lens centering problem is fully present at the level of the fitting cross, but is slightly diminished at the very top of the lens.

[GeauxTigers]

I agree that you should have had a seg height of 24 with this particular lens and that progressives have some serious limitations.... the optician who fit you should have put you into a varilux panamic which only requires a 18 seg height...

According to the OLA Progressive Identifier, the recommended fitting height for the Essilor Natural is 18, the same as the Panamic. My seg height is 20. Is OLA incorrect, or is Essilor being, let's say, creative?

however there are alot of other types of progressives that the optician could have put you in that would have worked better than the natural you were fitted with... also like i said in my previous post i think you should double check the left eye fitting cross...

But it's rotating the left lens that fixes it. It's the right eye that improves when I look through a spot 3mm temporal to the fitting cross.

part of the frustration of this business is when you hand someone a new pair of glasses and the patient says after wearing the glasses for not even a minute that they cannot see out of them... without giving them a try first (wearing for at least a week) also the adaption period for a first time progressive wearer is 2 weeks to adapt to the new type of lens... I am not saying that you should just accept poor vision... I am saying give it some time and then if your still having problems go back and let them know about it... if they are any kind of reputable outfit they will help you...

Look, I'm well aware that different is not necessarily bad, which is why I refuse to pass judgment right there in the store. I don't say they're good or bad; I say, "I"ll have to go home and wear them for a while before I know." This is true for both vision and feel of the frames on my head. I'm not complaining about poor peripheral vision, or swimming distortions as I turn my head, or difficulty looking at my feet when I descend stairs, or narrow reading area. I'm describing problems looking straight ahead through the centers of the lenses at points 30" and beyond that are corrected when I rotate the left lens and gaze through a point 3mm temporal to the fitting cross on the right lens. I don't believe these are problems I will adapt to. Similar problems have affected other pairs made by different labs over the past two months, and I wore those glasses for up to a week before I got tired of walking around and working at my computer with my head pointed left so I can look straight ahead through the sharpest part of the right lens. If I could only have kept the left lens rotated at the same time, man, would I have been in business!

[Chris Ryser]

Would you rather we just accepted our spectables as is? ............................

Can I see better or worse. If worse, something is not right. JMHMO -

My comment about myps was not meant to insult you. It was meant towards the opticians who should know that a myop takes off his glasses and checks the freshly purchased glasses without the magnifier which he does not need.

Look at the rtest of my comments and think about it if there is any validity in my technical points. I learned already when progressives were introduced 48 years ago that they should and could not be sold just to anybody out of many diggerent reasons. At the time they were made by only one company who owned the patents and could afford to miss out on a sale.

These days everybody can make them and plenty companies do. In principle they are all the same some with minimal and marginal variations.

Your problem is that your optician maybe should NOT have sold you these lenses in that frame, but tried his best and it did not work out, and very probably none of them will. Your seg height is too low and the add is to high to jump in this type of vision correction. You can not tolerate the distortion toward the side, you have a reading part that is too small and too far down and too small because it had to be cut off in order to fit the frame.

According to the ESSILOR (the originators of the modern progressive lens)spokesman on this Optiboard, only 45% of bifocal wearers are looking through progressive lenses. 55% are using the other means = a regular bifocal.

People give up a lot of personal comfort in order to look trendy, but it does not always work out for everybody and you could be one of them.

See an independant optician who has had proper schooling in his profession plus quite some years of expirience and he will probably be able to look into your problem from more than just the RX side.

With a good Rx for distance you see well in single vision lenses, when you take off your glasses you see equally well without glasses. When you wear your progressives you will expierience a different world of vision. If the lenses are done right they are not the type you should wear.

[slaboff]

originally when the natural and varilux comfort came out the minimum fitting height was 24mm, when the newer style lenses came out that had seg height minimums of 18 they changed their story and said it could be fit at 18 mm ? whenever i tried to fit this lens at 18 mm with patients i had a high non adapt rate, so i went back to the 24mm minimum... so what is the real proper fitting height... i think its 24 and essilor just changed it without changing the lens design (to my knowledge) thats why we are saying a 24 seg ht is appropriate...in my post i also did not say that you didnt give it enough time i was talking hypothetically about patients we see on a regular basis that do not give it enough time...

[Jedi]

Regarding progressive seg. ht, many opticians confuse minimum fitting hts. with recommended fitting hts. Now, many manufacturers don't do anyone any favors by advertising min. hts. A lens fit at the minimum fitting ht. will contain half of the reading area or enough for most patients to accomadate. A lens fit a few mm higher will deepen the reading area, which can often solve problems with patients "hunting" for the reading area, as it has moved up from the bottom of the frame.

In all honesty I would rather move the seg higher to increase the depth of the reading area than fit at the minimum ht. remember most PALs have a drop of 2-6mm before progression begins raising the ht. a mm or two will often be undetectable in the distance but benefit gretly in the reading. Now remember this is not how I fit PALs in general but in special circumstances with the patients KNOWLEDGE it can be quite beneficial.

Sorry to thread-jack

[GeauxTigers]

Regarding progressive seg. ht, many opticians confuse minimum fitting hts. with recommended fitting hts. Now, many manufacturers don't do anyone any favors by advertising min. hts. A lens fit at the minimum fitting ht. will contain half of the reading area or enough for most patients to accomadate. A lens fit a few mm higher will deepen the reading area, which can often solve problems with patients "hunting" for the reading area, as it has moved up from the bottom of the frame.

In all honesty I would rather move the seg higher to increase the depth of the reading area than fit at the minimum ht. remember most PALs have a drop of 2-6mm before progression begins raising the ht. a mm or two will often be undetectable in the distance but benefit gretly in the reading. Now remember this is not how I fit PALs in general but in special circumstances with the patients KNOWLEDGE it can be quite beneficial.

Sorry to thread-jack

Again, my seg height is 20mm, which is 2mm more than the recommended fitting height for Essilor Natural, and I'm not having a problem with the reading area, which is actually rather decent. The first pair (by Sears, lo those many weeks ago) got the seg height a few mm too small, and the difference between those glasses and my current ones is like night and day WRT the reading portion.

[Jedi]

Sorry to thread-jack

I was posting more of a "side bar", than anything in reponse to your initial posting.

[GeauxTigers]

I was posting more of a "side bar", than anything in reponse to your initial posting.

I understood that from your earlier "thread-jack" disclaimer. However, my purpose in coming here was to elicit some useful new information and advice, hopefully from expert opticians and/or optometrists, and I've spent considerable time trying to state my observations precisely and in detail. The danger in the last few messages in this thread is that people who might be capable of answering my questions will see these non-responsive replies and conclude I'm just a "reluctant adapter," which, at the very start of my initial message, I tried to establish I'm not. That's why I replied to your message and a couple of others today, to indicate they don't address my problem, and they're diluting my message.

[Ryan]

I am going to ask a basic question or two, what is the material (polycarb, CR-39. hi-index?) This as well as you might as well have the base curves checked against the old glasses. This is a typical OD question

[GeauxTigers]

I am going to ask a basic question or two, what is the material (polycarb, CR-39. hi-index?) This as well as you might as well have the base curves checked against the old glasses. This is a typical OD question

Hi Ryan, these are Essilor Natural polycarbs. The old SV glasses (circa 2001) are whatever polycarb Lenscrafters was using for "Featherwates" at the time.

[Texas Ranger]

first off, a +1.00-4.25 rx is not for a MYOPE. the rx has +1 in one meridian and a -3.25 90 degreesw away, a difference of 4.25, so they do not see up close well without their glasses. special glasses for the pc would be of great use, but you do need to have eyewear that if properly rxd and made right. I think we all consider that the axis is not prescribed right for the left lens, and that the right lens has the plane of the cylinder ground 3mm wide. these things can be fixed easily enough. sometimes base curves can cause problems, sometimes we see that +1.00 and get too steep a base curve; the pal needs to have more depth, but it would require a deeper frame, which is up to you.. I would stay with cr-39 instead of poly, the panamic design deal with equilibrium like no other lens, sometime docs rx an extra +0.25 IF the patient, but this is not generally correct, it just makes for a design that is harder to adjust to. so, back off the add to +1.25. Now, i'm a big proponent of Crizal AR lenses, especially with high cylinders, since they create so much ghost image problems. also, when we have a frame 'b' measurement of 31, with a pal design, and a mostly distance rx, it's just too shallow...print this and take it with you to your eye doc...Martello had a great idea, have them do a sv distance rx, about 50mm round, spot the axises, and let you turn it to where you see the best, and note that...could save a lot of redoing...you just cannot emulate your rx in a trial frame...or phoropter.

[GeauxTigers]

first off, a +1.00-4.25 rx is not for a MYOPE. the rx has +1 in one meridian and a -3.25 90 degreesw away, a difference of 4.25, so they do not see up close well without their glasses.

Give that man a cigar. :)

special glasses for the pc would be of great use, but you do need to have eyewear that if properly rxd and made right. I think we all consider that the axis is not prescribed right for the left lens, and that the right lens has the plane of the cylinder ground 3mm wide.

This "cylinder plane" bit - I take it that's different than the position of the fitting cross, which does appear to be correctly positioned? How is it different labs made a similar mistake on this lens, and what I can I tell the optician? She'll definitely work with me, and I plan to see her in the next day or two.

these things can be fixed easily enough. sometimes base curves can cause problems, sometimes we see that +1.00 and get too steep a base curve; the pal needs to have more depth, but it would require a deeper frame, which is up to you.. I would stay with cr-39 instead of poly, the panamic design deal with equilibrium like no other lens, sometime docs rx an extra +0.25 IF the patient, but this is not generally correct, it just makes for a design that is harder to adjust to. so, back off the add to +1.25.

I've never really stopped questioning bumping the add from +1.25 to +1.50, which the OD did at the same time she specified a higher seg height for the first pair, and it's been +1.50 ever since. Backing off seems worth a try.

About the plastic lens, it wasn't offered to me, and I don't know if it's available. Is it possible to predict how much thicker and heavier it will be than the polycarbs, which are about 4mm thick at their thickest point, at the bottom of the right lens?

Now, i'm a big proponent of Crizal AR lenses, especially with high cylinders, since they create so much ghost image problems. also, when we have a frame 'b' measurement of 31, with a pal design, and a mostly distance rx, it's just too shallow...print this and take it with you to your eye doc...Martello had a great idea, have them do a sv distance rx, about 50mm round, spot the axises, and let you turn it to where you see the best, and note that...could save a lot of redoing...you just cannot emulate your rx in a trial frame...or phoropter.

I'll ask! This has really come to puzzle me, as I've never had glasses remade in my life, and I've been wearing glasses forever. Is it possible that refraction performed under the very artificial conditions of the doctor's office just isn't quite sensitive enough? I mean, if the OD ends up with 2-3 choices which I can't distinguish there, how likely is it they are significantly different in the real world, such as looking at a monitor or a news channel crawl? Maybe the 167 axis from 1993 was the "right" one, and the 165 axis from 2001 was tolerable, but I notice a big difference in the current 162? I made a spreadsheet of these changes which I'm going to bring with me when I see the optician, and if need be, my current OD or a new one for a second opinion. Thanks for your help.

[Joann Raytar]

I'll ask! This has really come to puzzle me, as I've never had glasses remade in my life, and I've been wearing glasses forever. Is it possible that refraction performed under the very artificial conditions of the doctor's office just isn't quite sensitive enough?

Wasn't for me once. We ended up with a different prescription once when the Doctor set me up with a trial frame and had me go out of the exam room and look around.

[shellrob]

My question for Geauxtiger is: Are you an Optician yourself?

[GeauxTigers]

Wasn't for me once. We ended up with a different prescription once when the Doctor set me up with a trial frame and had me go out of the exam room and look around.

I did that today; unfortunately, it wasn't very helpful, as the only computer screens they had to look at were plain old text mode DOS. If only they had TVs running CNN and Trinitron CRTs running Windows XP... :)

I did get a second opinion today, and the refraction, done from scratch, and without the new doc knowing what my old Rx was, did come out a bit different, with the OS axis and OD sphere more in line with my old glasses. So I'm having the progressives made one last time before giving up and moving on to bifocals.

The strange thing was, the tech measured the axis on my current 2001 glasses, which are good for distance, and she found the OS axis was 169 (was supposed to be 165 per 2001 Rx). The doc earlier had me try an axis of 170 in trial frames, and it was horribly blurry. So something's amiss there. Anyway, I'm hoping that going from 162 to 165 (what the doc measured today) will split the difference and end up clear.

[GeauxTigers]

My question for Geauxtiger is: Are you an Optician yourself?

Nope.