Medical Forum / General / Vision / December 2006
new progressives - narrow field close up
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ATHiker95 - 01 Dec 2006 21:22 GMT I'm new to glasses, having used reading glasses for the past 10 years or so. I got a pair of progressives today and whereas they seem ok at distance and mid range, reading a book, it seems that my field of sharp vision is about 4 words across. If I were in the middle of the line, the edges on both sides would appear blurry. If I turn my head to look at the end of the line, it will get better, but it is almost like I need to tilt the book towards me as well - something that makes me think I have to be in the direct plane of focus. Either that or move the book back and forth from right to left and vice versa to make it sharp. Am I nuts? Will my eyes adjust to this? Of course the optician guy said wear them for 2 weeks and see how it goes.
I'm a fairly fast reader so normally am used to skimming my eyes across the page - now I I feel like I have to be moving my head back and forth constantly. When I do move my head to look at the right or left side of the page, vertical lines skew. I have to physically move the book or magazine directly under my vision to make the vertical lines vertical again.
Thoughts?
Thanks, Mark
Dr Judy - 01 Dec 2006 21:27 GMT > I'm new to glasses, having used reading glasses for the past 10 years > or so. I got a pair of progressives today and whereas they seem ok at [quoted text clipped - 14 lines] > magazine directly under my vision to make the vertical lines vertical > again. Although progressives do have narrower fields than readers, this is too narrow. Return to your fitter and explain the problem. The frames likely need adjusting; the centre may be wrong or you may need a different brand of lenses.
Dr Judy
Dan Abel - 01 Dec 2006 22:13 GMT > think I have to be in the direct plane of focus. Either that or move > the book back and forth from right to left and vice versa to make it > sharp. Am I nuts? Will my eyes adjust to this? Of course the optician > guy said wear them for 2 weeks and see how it goes. I think the two week thing might be a good idea. I've done the "move the book back and forth thing" though, and it is totally unacceptable. Moving your head is also unacceptable.
 Signature Dan Abel dabel@sonic.net Petaluma, California, USA
ATHiker95 - 01 Dec 2006 22:23 GMT I remember the optician said " you have to learn to point your nose at what you are looking at" , which of course would mean you would be moving your head back and forth. What is really distracting is when you move your head outside of your 3 or 4 word zone of comfort to point to the next 3-4 words to read and the page starts twisting - vertical line skew,etc.And that's even when you move your head to point to that section! It's like you have to move the magazine or book back to the left so that it is directly under your line of vision, which of course is a nutty thing to have to do. Maybe this is all normal, but like Doc Judy mentions here, maybe this is not quite right either.
Mark
> > think I have to be in the direct plane of focus. Either that or move > > the book back and forth from right to left and vice versa to make it [quoted text clipped - 4 lines] > the book back and forth thing" though, and it is totally unacceptable. > Moving your head is also unacceptable. David Combs - 22 Dec 2006 01:19 GMT >I remember the optician said " you have to learn to point your nose at >what you are looking at" ... THAT is why I like "executives"!
With executives, your head stays fixed, and you look left and right BY SWIVELLING YOUR EYES --
just the way nature (evolution) *designed* them to work!
David
Mark A - 01 Dec 2006 22:42 GMT > I'm new to glasses, having used reading glasses for the past 10 years > or so. I got a pair of progressives today and whereas they seem ok at [quoted text clipped - 19 lines] > Thanks, > Mark Please post your exact Rx, the lens brand (Sola, Essilor, Varilux, Zeiss, etc), the lens model (Liberty, Panamic, Comfort, etc), and the type of material (polycarb, 1.60. 1.67 etc). If you don't know this information, contact your optician and find out. If the person you talk to does not know, ask to speak to someone in charge.
ATHiker95 - 02 Dec 2006 03:06 GMT I bought them at Costco. Progressive Hi-index 1.67 - Ovation.
DIST: SPHERE CYL AXIS R +7.50 -.750 95 L +7.50 -.750 97
ADD: ADD SEG HGT DIST P.D.
R 2.25 19.0 29.0 L 2.25 19.0 31.0
> > I'm new to glasses, having used reading glasses for the past 10 years > > or so. I got a pair of progressives today and whereas they seem ok at [quoted text clipped - 25 lines] > information, contact your optician and find out. If the person you talk > to does not know, ask to speak to someone in charge. Mark A - 02 Dec 2006 03:53 GMT >I bought them at Costco. Progressive Hi-index 1.67 - Ovation. > [quoted text clipped - 8 lines] > R 2.25 19.0 29.0 > L 2.25 19.0 31.0 That is a very tough Rx because of its high strength. You are looking at +9.75 in the reading area, which is quite powerful, and difficult for progressives to handle well and provide a wide reading area.
On top of that, you have 1.67 index (the higher the index, the more chromatic distortion). But high index lenses make the lens thinner and therefore lighter. If you don't care about thin and light, then you might be able to try a 1.60 index lens.
On top of that, the Essilor Ovation.you have is not a "premium " lens design Essilor does own a premium brand called Varilux, and Varilux has some good premium designs such as Physio360. Of course, these will cost more, but if want better vision you will need a premium progressive lens design with your powerful Rx. Other premium brands besides Varilux include Zeiss, Rodenstock, Hoya, and others.
Since you should have a 30 day adaptation guarantee, you should ask Costco what other brands and models they have and try a remake (if you can afford the premium brands), or get a full refund if that is an option (not all optical stores have a money-back guarantee).
But don't expect perfection will any progressive lens that is that powerful. Ultimately, you will have to learn to move your head to some degree, unless you want bifocals (with visible lines).
PS: Don't let anyone talk you into polycarb lens material. For very high power plus (+) Rx like yours, polycarb is horrible in terms of optical quality.
Liz Day - 02 Dec 2006 04:06 GMT A friend with progressives described reading with them as being "like eating corn on the cob". He never found any that were different. I don't know his scrip. LD
Mark A - 02 Dec 2006 06:00 GMT >A friend with progressives described reading with them as being "like > eating corn on the cob". > He never found any that were different. I don't know his scrip. > LD There definitely is a difference between the low-end progressive lens designs and the high-end designs, but there are not any progressives that allow one to not move your head at all while reading. One will eventually learn to move the head by instinct and it becomes second nature, but obviously it helps to start with a reasonably wide reading area to begin with, and that usually means a premium lens design for someone with a high power Rx.
ATHiker95 - 02 Dec 2006 14:25 GMT I screwed up and didn't notice it when I entered my script. Under Sphere for Right and left it was supposed to read +.75, NOT +7.50. I suspect that will make a difference in what you might tell me. :) Sorry about that! Missed it completely!
Mark
> >A friend with progressives described reading with them as being "like > > eating corn on the cob". [quoted text clipped - 8 lines] > with, and that usually means a premium lens design for someone with a high > power Rx. Mark A - 02 Dec 2006 14:40 GMT >I screwed up and didn't notice it when I entered my script. Under > Sphere for Right and left it was supposed to read +.75, NOT +7.50. I > suspect that will make a difference in what you might tell me. :) > Sorry about that! Missed it completely! > > Mark In that case, the optician was negligent in selling you a 1.67 index lens. Get a remake with 1.50 regular plastic (CR-39). If for some reason you must have a higher index, then go with 1.60 at the highest. Even though you have a mild Rx, I would stay away from polycarb given your previously problems and the plus (+) lens power.
Try a premium lens design like Varilux Physio360 (or at least some Varilux model). Hopefully Costco has other premium lens designs also.
But you will have to learn to move your head a little (you will "adapt" over time).
ATHiker95 - 02 Dec 2006 15:14 GMT Thanks for the advice! I don't mind moving my head so much, more bothersome at this point is the fact that as I turn it ever so slightly to see the end of the line, I can see the page skewing (sort of a visual distortion) and the left edge of the book tilts both along the vertical and horizontal axis. Maybe I will adjust to that or maybe that is just something not quite right - think I'll drop in on them today and ask.
Mark
> >I screwed up and didn't notice it when I entered my script. Under > > Sphere for Right and left it was supposed to read +.75, NOT +7.50. I [quoted text clipped - 14 lines] > But you will have to learn to move your head a little (you will "adapt" over > time). Mark A - 02 Dec 2006 15:33 GMT > Thanks for the advice! I don't mind moving my head so much, more > bothersome at this point is the fact that as I turn it ever so slightly [quoted text clipped - 5 lines] > > Mark It doesn't make much sense to ask someone at Costco who sold you 1.67 index lenses for advice, because they are idiots (or maybe they are cheats who wanted to sell you a more expensive lens).
Almost all places allow for a free remake or refund if you are not satisfied (which is why progressives are so expensive). You will have much better optics and vision with a lower index lens lens. 1.67 is only needed for people with high power Rx who want thinner lenses (the higher the Rx, the thicker the lens). With your very mild Rx, 1.67 will not make it noticeably thinner, but will just make your vision worse.
A premium lens design (Varilux, etc) in 1.50 plastic will probably cost about the same (or maybe lower) than Ovation in 1.67.
ATHiker95 - 02 Dec 2006 16:34 GMT I knew that cr39 plastics were definitely better than polycarbs before I went in. I found a pair of frames I liked that wire rimless on the bottom. I was going to go with the cr39, but the optician said that Costco wouldn't sell a rimless pair with cr39 because they had too many problems with the bottom of the lens chipping (I guess when people lay them down or something - don't fully understand how that happens). Then he went on to say how the 1.67 was excellent, blah, blah, high abbe and all that (I read now on the Net that cr 39 has an abbe of 58 and abbes for high and medium-index fall in the 35-45 range.)
But nonetheless, I've dropped $200 on these things and I figure I'll go back and lay the problem on their doorstep and see if they can make it right.
> > Thanks for the advice! I don't mind moving my head so much, more > > bothersome at this point is the fact that as I turn it ever so slightly [quoted text clipped - 19 lines] > A premium lens design (Varilux, etc) in 1.50 plastic will probably cost > about the same (or maybe lower) than Ovation in 1.67. Mark A - 02 Dec 2006 21:55 GMT >I knew that cr39 plastics were definitely better than polycarbs before > I went in. I found a pair of frames I liked that wire rimless on the [quoted text clipped - 9 lines] > back and lay the problem on their doorstep and see if they can make it > right. 1.67 has an abbe value of about 32-26 at best (Sola 1.67 has a abbe value of 32 in their 2006 catalog). The term "high index lens" has no meaning whatsoever these days, because the term was originally coined when 1.60 was the highest plastic index available.
I just called my local Costco, and (after getting past the first idiot who didn't know the different between a lens brand and a lens material) they said that Costco only sells one brand of progressive lens (Essilor Ovation) and only 2 materials (polycarb and 1.67). So the person who told you that they don't sell CR-39 because of chipping on your type of rimless frame was lying. The don't sell CR-39 for any frames.
Looks like you are screwed. Even Wal-Mart has a much better selection of lenses than Costco.
ATHiker95 - 03 Dec 2006 01:53 GMT Interesting, as I certainly got the impression from my Costco that I could get CR-39's. Anyway, I took mine back today and sat down with a very nice woman who checked my pd again using a cpr and told me that the previous readings were incorrect and mentioned that something else was incorrect as well, so no wonder I was having some issues. So she is having them redone and we'll see how this saga continues. Not surprised after hearing that, that I was having skewing of the page when glancing to the right. What will be interesting to see is how much of a single line appears in focus when I get them back - hopefully a bit more than 3-4 words.
Mark
> >I knew that cr39 plastics were definitely better than polycarbs before > > I went in. I found a pair of frames I liked that wire rimless on the [quoted text clipped - 24 lines] > Looks like you are screwed. Even Wal-Mart has a much better selection of > lenses than Costco. Mark A - 03 Dec 2006 02:12 GMT > Interesting, as I certainly got the impression from my Costco that I > could get CR-39's. Anyway, I took mine back today and sat down with a [quoted text clipped - 8 lines] > > Mark I suspect that they sell CR-39 for SV lenses, but not for Essilor Ovation progressives. That is strictly a Costco decision, since Essilor makes the Ovation in CR-39.
David Combs - 22 Dec 2006 01:37 GMT >Thanks for the advice! I don't mind moving my head so much, more >bothersome at this point is the fact that as I turn it ever so slightly >to see the end of the line, I can see the page skewing (sort of a >visual distortion) and the left edge of the book tilts both along the >vertical and horizontal axis. Maybe I will adjust to that or maybe Well, so much for any more speed-reading!
Well, I guess there is a way to preserve that ability but *without* having to twist your head left and right:
Simply read a COLUMN of three or four words (whatever the progressives allow without twisting the head) DOWN the page,
and MEMORIZE column-width of each line's worth of words (eg your 3 or 4), the column going from the top of the page to the bottom of it, then twist your head the angle necessare to grab the next three or four words, and go down that column, etc,
and when you get finished, just mentally sort them out and reconstitute the original lines, and (mentally) read *those*!
(Damn, I should PATENT that!)
David
PS: I'm quite happy with executives -- no twisting needed.
David Combs - 22 Dec 2006 01:29 GMT >"ATHiker95" <mholmes@gmail.com> wrote in message > [quoted text clipped - 13 lines] >powerful Rx. Other premium brands besides Varilux include Zeiss, Rodenstock, >Hoya, and others. In what way is a premium "design" different-from/better-than a non-premium?
(other than a simple "you can see better with them")
Like, how does the (solid) geometry/topology(non-math usage) differ between them?
Also, since presumably these things are gound "by machine", does it really cost much more to *make* and/or grind them?
(If they do cost the same to make, but they charge wildly different prices for them, then it really seems like a quite nasty GREED for them to *knowingly* and *deliberately* sell you a (relatively)-inferior lens unless you pay them a lot more?)
Actually, what *is* the situation?
Thanks,
David
Greg - 02 Dec 2006 16:37 GMT > I bought them at Costco. Progressive Hi-index 1.67 - Ovation. Ovation is a fairly low-end lens. Essilor sells a ton of them to places like Costco and the "2 pair for $199" places, but they are far from their best design. I had a set and had to junk them in favor of Varilux because they just were unacceptable, with many of the same symptoms you describe.
Robert Martellaro - 02 Dec 2006 22:45 GMT >I'm new to glasses, having used reading glasses for the past 10 years >or so. I got a pair of progressives today and whereas they seem ok at [quoted text clipped - 19 lines] >Thanks, >Mark I believe that Costco only sells the Ovation- pretty much one size fits all. Great prices though.
You're going to be aware of the optical boundaries of any PAL with a +2.25 add if this is your first multifocal, even if the lenses are properly positioned. Some designs, when positioned optimally, will allow the brain to adapt much faster, with potentially wider fields of vision.
Hope this helps,
Robert Martellaro ~~~~~~~~~~~~~~~~~~ Optician/Owner Roberts Optical Wauwatosa, Wi. ~~~~~~~~~~~~~~~~~~ "Science is a way of trying not to fool yourself." - Richard Feynman
ATHiker95 - 03 Dec 2006 01:55 GMT Robert, When you say "some designs", what do you mean by that?
Thanks, Mark
> >I'm new to glasses, having used reading glasses for the past 10 years > >or so. I got a pair of progressives today and whereas they seem ok at [quoted text clipped - 38 lines] > "Science is a way of trying not to fool yourself." > - Richard Feynman Robert Martellaro - 04 Dec 2006 20:10 GMT >Robert, >When you say "some designs", what do you mean by that? > >Thanks, >Mark Mark,
Hard and soft designs, which describes how the surface astigmatism is spread out over the lens, short, medium and long corridors, or the distance from the far vision to the near portion of the lens, multi-designs might have a variable inset according to the add and distance power, and may be optimized for position of wear e.g. vertex distance, panto etc. Moreover, lens designers use ray tracing to develop methods to control off-axis aberrations, which might involve free-form technology, producing complex surfaces that are not possible with traditional surfacing equipment.
Hope this helps,
>> You're going to be aware of the optical boundaries of any PAL with a +2.25 add >> if this is your first multifocal, even if the lenses are properly positioned. >> Some designs, when positioned optimally, will allow the brain to adapt much >> faster, with potentially wider fields of vision. >> >> Hope this helps,
>> Robert Martellaro >> ~~~~~~~~~~~~~~~~~~ [quoted text clipped - 4 lines] >> "Science is a way of trying not to fool yourself." >> - Richard Feynman Robert Martellaro ~~~~~~~~~~~~~~~~~~ Optician/Owner Roberts Optical Wauwatosa Wi. ~~~~~~~~~~~~~~~~~~ "An expert is a person who has made all the mistakes that can be made in a very narrow field." - Niels Bohr
Mark A - 04 Dec 2006 20:40 GMT > Mark, > [quoted text clipped - 14 lines] > > Hope this helps, In layman's terms, that means that some lens designs are more sophisticated than others. Essilor Ovation is not one of the more sophisticated designs. Essilor's premium brand of progressives is called Varilux, and within that brand there are various models, some more sophisticated than others.
jeff.prentice@gmail.com - 15 Dec 2006 07:51 GMT Im having the same problem. I just paid $650 for Shamir autograph freeform progressive lenses - the frames were extra - the total cost with frames was around $875.00
I paid that much because I was assured that this would give me the widest horizontal range, with this 'new' advanced technology. However, although the distance is fine, the midrange is very small - I can't look at a newspaper on the table without the edges being blurred. To view my computer monitor I have to peer through a tiny slit and move my head back and forth. The near is very small as well- I believe this is because I wanted more distance at the top - I tend to hold my head back. If I increase the near I will lose the far.
The optometrist told me this was normal, and that progressives were a compromise, and that I would need reading glasses, and computer glasses. But I feel like I could have gotten a lens from lenscrafters or costco that would have been just as good.
The seller told me I could bring them back for any adjustment - but since I have never worn progressive, I dont know what normal is.
2 progressive wearers I have talked to since say they dont have any issues at all with blur- and they got lenses from places like lenscrafters.
Any advice?
Mark A - 15 Dec 2006 22:56 GMT > Im having the same problem. I just paid $650 for Shamir autograph > freeform progressive lenses - the frames were extra - the total cost [quoted text clipped - 22 lines] > > Any advice? The useable portion of any progressive lens looks about like an hour glass, although maybe a little wider at top for distance vision. The transition area for intermediate vision in the middle of the lens is the narrowest part of the usable lens. Even the reading area is relatively small (a maximum of about 1/3 the width of the lens at the very bottom, and even narrower if you have a very short frame).
As to whether you need an advanced lens design like the Shamir Autograph, or whether you would notice the difference between a lower priced design from Costco or Lenscrafters, is hard to say, especially since you did not post your complete Rx. The advance designs usually help people with a high power Rx the most, and most people with a high power Rx can tell the difference. If you have a weak Rx, then the very expensive high-tech designs might not be worth the extra cost.
There are also designs that are better than available at Costco or Lenscrafters, but are still much less expensive then the custom made lenses that you have. Examples would include the Varilux Comfort or Panamic, Rodenstock Progressive Life 2, etc.
jeff.prentice@gmail.com - 17 Dec 2006 10:18 GMT The useable portion of any progressive lens looks about like an hour glass,
> although maybe a little wider at top for distance vision. The transition > area for intermediate vision in the middle of the lens is the narrowest part > of the usable lens. Even the reading area is relatively small (a maximum of > about 1/3 the width of the lens at the very bottom, and even narrower if you > have a very short frame). I think I was mislead by the advertising and the sales talk - look at the shamir description: "Shamir Insight, Inc.’s Autograph™, a personalized mid-corridor design, uses Prescriptor™proprietary software to maximize distance, intermediate, and near viewing zones while virtually eliminating swim and distortion. The Autograph PAL has a very wide vision area."
It aint that wide from what I can see and there is swim and distortion - Its a little like false advertising so far - Im on my third day and Im not in love with these things - But I dont look forward to trifocals again -
I have to choose between seeing the world in three sections or looking through an expensive fishbowl (:
My RX is fairly weak I think
Sphere right +0.50 Cylinder -1.25 Axis 096 Add +2.00 Sphere left +0.50 Cylinder -1.25 Axis 095 Add +2.00
The question also is why do some progressive wearers say they DONT have blurred edges when looking at a newspaper - mine is very noticable - like a 5 word span. OR are they looking thru a c/u - near - reading part of the lens? Im wondering if I need to have the near moved up so I can at least read, because the very very lowest part of the lens seems to widen? OR will that have me peering through the tops to see distance since I have moved the entire focal point up?
The optician says the field of vision will widen as the brain adjusts
I also have the option of taking them back and trying to have the cheaper lenses put in - although I dont know return policies - arent nonadjust returns only replaced with trifocal or bofocal equivalents?
at the very worst Im stuck wth an expensive progressive that is more than I need - but i do want to make sure it was manufactured correctly and fitted so I am seeing what I am supposed to be seeing. According to their ads I should be seeing things wider, with less distortion
Mark A - 17 Dec 2006 15:55 GMT The useable portion of any progressive lens looks about like an hour glass,
> although maybe a little wider at top for distance vision. The transition > area for intermediate vision in the middle of the lens is the narrowest [quoted text clipped - 4 lines] > you > have a very short frame). I think I was mislead by the advertising and the sales talk - look at the shamir description: "Shamir Insight, Inc.'s AutographT, a personalized mid-corridor design, uses PrescriptorTproprietary software to maximize distance, intermediate, and near viewing zones while virtually eliminating swim and distortion. The Autograph PAL has a very wide vision area."
It aint that wide from what I can see and there is swim and distortion - Its a little like false advertising so far - Im on my third day and Im not in love with these things - But I dont look forward to trifocals again -
I have to choose between seeing the world in three sections or looking through an expensive fishbowl (:
My RX is fairly weak I think
Sphere right +0.50 Cylinder -1.25 Axis 096 Add +2.00 Sphere left +0.50 Cylinder -1.25 Axis 095 Add +2.00
The question also is why do some progressive wearers say they DONT have blurred edges when looking at a newspaper - mine is very noticable - like a 5 word span. OR are they looking thru a c/u - near - reading part of the lens? Im wondering if I need to have the near moved up so I can at least read, because the very very lowest part of the lens seems to widen? OR will that have me peering through the tops to see distance since I have moved the entire focal point up?
The optician says the field of vision will widen as the brain adjusts
I also have the option of taking them back and trying to have the cheaper lenses put in - although I dont know return policies - arent nonadjust returns only replaced with trifocal or bofocal equivalents?
at the very worst Im stuck wth an expensive progressive that is more than I need - but i do want to make sure it was manufactured correctly and fitted so I am seeing what I am supposed to be seeing. According to their ads I should be seeing things wider, with less distortion
Mark A - 17 Dec 2006 16:18 GMT > I think I was mislead by the advertising and the sales talk - look at > the shamir description: [quoted text clipped - 34 lines] > and fitted so I am seeing what I am supposed to be seeing. According to > their ads I should be seeing things wider, with less distortion The term "wide" is relative. They mean wide relative to other progressives, and in this case they are talking about very small areas of useable vision to begin with. Over time, you will learn to adapt to the distortion and "swim" effect so that it does not bother you as much; however, the width of the reading area is not likely to increase.
The problem could be because of a poor fitting (the optical center of the lens is not positioned correctly for the way the frame sits on your face), or you have very short frames (short frames are fashionable, but they decrease the amount of the reading area). But I am not sure that 5 words across is that far out of line for a progressive in terms of being in sharp focus.
For your relatively mild Rx, the Shamir autograph is probably way overkill. You did not mention what type of material was used (1.50, polycarb, 1.67, etc), and you should not use a high index material (nor should you use polycarb) for such a weak Rx. The higher the index of the material, the worse is the optical properties of the lens. Regardless of index, polycarb has the worst optical qualities of any commonly prescribed lens material (but it is a “safety” lens that a lot of opticians like to use on drilled frames because it lowers the risk of the lens cracking).
Robert Martellaro - 20 Dec 2006 20:30 GMT >The useable portion of any progressive lens looks about like an hour >glass, [quoted text clipped - 3 lines] >> about 1/3 the width of the lens at the very bottom, and even narrower if you >> have a very short frame). Mark as covered this quite well, I'll just add a few additional comments.
>I think I was mislead by the advertising and the sales talk - look at >the shamir description: The marketing departments of the optical manufactuers are hard at work trying to sell their products to the optician. It's the optician's responsibility to sift through the hype and try to make recommendations to their clients based on science and subjective experience.
>"Shamir Insight, Inc.s Autograph, a personalized mid-corridor >design, uses Prescriptorproprietary software to maximize distance, >intermediate, and near viewing zones while virtually eliminating swim >and distortion. The Autograph PAL has a very wide vision area." Reasonably accurate. But like Mark said, compared to what?
>It aint that wide from what I can see and there is swim and distortion >- Its a little like false advertising so far - Im on my third day and >Im not in love with these things - But I dont look forward to trifocals >again - I agree with your optician- after some period of time (less than a month) you'll have difficulty seeing the boundaries and swim.
>I have to choose between seeing the world in three sections or looking >through an expensive fishbowl (: See the above, although the position of the lens plays a significant role in how noticeable the distortions will be from the wearers perspective. I'll have to assume this was done properly.
>My RX is fairly weak I think > >Sphere right +0.50 Cylinder -1.25 Axis 096 Add +2.00 >Sphere left +0.50 Cylinder -1.25 Axis 095 Add +2.00 Pretty strong add power for a first time PAL (progressive addition lens) wearer- the stronger the add the greater the aberrations. If you were wearing segmented multfocals (lined trifocals) I would have made you twist my arm to switch to PALs.
>The question also is why do some progressive wearers say they DONT have >blurred edges when looking at a newspaper - mine is very noticable - [quoted text clipped - 3 lines] >to widen? OR will that have me peering through the tops to see distance >since I have moved the entire focal point up? The fitting cross (reference mark on the lens/template) should be central pupil when the gaze is straight ahead in a relaxed standing position. That shouldn't be tampered with.
>The optician says the field of vision will widen as the brain adjusts > >I also have the option of taking them back and trying to have the >cheaper lenses put in - although I dont know return policies - arent >nonadjust returns only replaced with trifocal or bofocal equivalents? I would wear them at least 2 weeks. You might want to get a second opinion on the lens position.
>at the very worst Im stuck wth an expensive progressive that is more >than I need - but i do want to make sure it was manufactured correctly >and fitted so I am seeing what I am supposed to be seeing. According to >their ads I should be seeing things wider, with less distortion One of the advantages of having the progressive portion on the back of the lens is that the reading area resides closer to the eye, resulting in less of a keyhole affect, with on paper at least, a wider field at near. I doubt you would see a difference unless you compared it to a more conventional and similar design like the Shamir Genesis. The atoric curves also increase fields and reduce aberrations, but is only noticeable if the astigmatism is about double (or more) than your Rx. The Autograph should feel slightly more refined when directly compared to the Genesis. That said, I would not have recommended this lens because the price to performance ratio is so low, at least in this application.
Hope this helps,
Robert Martellaro ~~~~~~~~~~~~~~~~~~ Optician/Owner Roberts Optical Wauwatosa Wi. ~~~~~~~~~~~~~~~~~~ "An expert is a person who has made all the mistakes that can be made in a very narrow field." - Niels Bohr
David Combs - 22 Dec 2006 02:00 GMT >The useable portion of any progressive lens looks about like an hour >glass, [quoted text clipped - 12 lines] > >It aint that wide By definition of "hour glass".
Although do note that they're other shapes, like for pilots (who (used to?) have to see all the dials and levers on the ceiling above their heads,
and there's ones optimized for lab-workers, etc
How do I know this? Because I was googling for bi and tri-focals, and hit upon one site that discussed these special needs, both for progressives and bi/tri-focals.
And though I thought I had bookmarked that site, I guess I didn't....
>The question also is why do some progressive wearers say they DONT have >blurred edges when looking at a newspaper - mine is very noticable - [quoted text clipped - 5 lines] > >The optician says the field of vision will widen as the brain adjusts Yeah, just like while watching a movie (in a theater) that's gone out of focus, with the projectionist gone -- well, worry not, your brain will adjust, and you'll soon again be seeing all the fine detail!
David
David Combs - 22 Dec 2006 01:50 GMT >> Im having the same problem. I just paid $650 for Shamir autograph >> freeform progressive lenses - the frames were extra - the total cost [quoted text clipped - 29 lines] >about 1/3 the width of the lens at the very bottom, and even narrower if you >have a very short frame). What I do for the computer is to use (1) executive (2) bifocals,
(3) with the "far" (ie top) part done for the distance of the computer screen (20-inch screen).
(4) and the "near" (ie bottom) part set for my "reading" distance.
For outdoors, eg driving, it's trifocals, again "executive", the relatively "short" mid-region ok for glancing down at the speedometer, gas guage, etc -- and the bottoms of course for reading maps, etc.
I really like the executive style -- and the "jumps" at the lines no problem (never were, even the first day).
Myself, I can see ZERO reason to go to progressives, although I can see MUCH reason for the shop to want me to get them, at what, three, four times the cost?
Note the clever marketing, via the word "progressive", implying "good", "modern", "out of the ordinary" (for "out of the ordinary" people too?).
Yeah, I'm being a wet blanket, but I've looked into these things for over ten years, and each time come up with the same result: not for me.
David
David
Dan Abel - 22 Dec 2006 17:10 GMT > For outdoors, eg driving, it's trifocals, again "executive", > the relatively "short" mid-region ok for glancing down > at the speedometer, gas guage, etc -- and the bottoms > of course for reading maps, etc. I don't understand this, and I think we have discussed this on the group before. I'm sure it depends on the car, but for the ones I've driven, It isn't a problem to see the dials on the dashboard. I've had the innards of my eyes surgically removed, and set for distance, so I am heavily dependent on reading glasses, but I can see things on the dashboard just fine. They are probably blurry, but most car makers aren't stupid, they design them so you can read them even if blurry. As you say, when it's time to read the map, then I have to stop and put on some glasses.
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