we are having problems whit high hyporopia +6 or more.
We are using Autograf 2 lenses ? ( we get them made at swisscoat)
we have changed one cutomer to essilor comfort short whit succes but why do they work better ?
best regards
Peter
we are having problems whit high hyporopia +6 or more.
We are using Autograf 2 lenses ? ( we get them made at swisscoat)
we have changed one cutomer to essilor comfort short whit succes but why do they work better ?
best regards
Peter
If they work better why not use them and not worry about it?
its a matter of price
With a +6 or higher, price shouldn't be an issue. Accept nothing less than the Hoya ID or the Zeiss Individual (Hoya ID will come out thinner and, more importantly, flatter though).
If the customer absolutely refuses to pay for the product you recommend, then there a few lens designs that should be 'ok'.
On the topic of why the comfort works... comfort always works.
Zeiss individual is not realy an option !!! they dont work at all, basicly the worst produkt we ever tried. but Hoya ID i dont realy know, only that the progression is devided on both surfaces so not the best design in my book, but oki i will try it out
best regards
Peter
Please explain why dividing the progression between the front and back is a negative... I've heard arguments that it makes no difference but never heard someone say it's inherently a bad thing. Personally I think it's a great idea.
The Individual is fine if dispensed correctly. We had major problems with it at first as well. But if you don't want to use it then the GT2 3D is fantastic... arguably better, even.
Ski: Ziess individual is the best progressive lens I have ever worn. Wish the coatings were as good as the optics.
Chip
Last edited by chip anderson; 07-10-2012 at 06:04 PM.
Zeiss coatings have improved a lot in the last few years... I would say they're quite good at this point in time. Our practice uses mostly Hoya and Zeiss lenses, and the Hoya coatings range is far, far superior.
But the lenses themselves are great.
A concave curve on the front of a progressive (convex) will increase distortion at a higher rate than on the back, in a myope. Anything on the front has more potential for a negative visual impact. The rate of distortion decreases for hyperopes. So at some point in very high hyperopes it makes sense to move some of the add to the front, thats why Zeiss does it for the Individual, as the back gets flatter. A concave curve on another concave curves still creates distortion, but at a lower amount.
95% of progressives are designed for Myopes because most patients are myopic. The change in Hyperopes involves prism through the corridor, because in a myope the inherant prism effect is out and away, for myopes in up and in (relative to the corridor). As the eye moves through the corridor, the virtual lens is moved relative to the eye.
There only 3 lenses in the US that compensate for this effect in the US. Zeiss Individual, Seiko Surmount, and Kodak Unique. They all take the near power, the distance power, the relation to OC and corridor lenght and redesign, and realign the corridor to compensate for prism using the near PD by moving the Virtual Lens closer to the true path that they eye is expected to take.
The Auto II have a very narrow corridor so its likely to see this effect in greater amounts, at lower powers.
+6.00 is inducing enormous amounts of unwanted prism as the eye travels through the lens and farther from the OC.
Although I love the GT2-3D for distance, its one of the best, I find the Intermediate, although wide, is at a very low angle so its terrible for my PC (laptops are good). As well, even in my 1.50 add the reading is the most narrow I have ever worn. Its great for cel phone or lap top users, but for PC users who read a lot, its terrible in my opinion.
Sharpstick,
Thank you for sharing your knowledge and experience with progressives. I find it fascinating and I learn a lot from the posts!
thats new for me that Auto II have a very narrow corridor, what lens does then have a wide corridor ? i once heard that Summit pro have a wide corridor it that true then ?
best regards
Peter
The Autograph 2 recommended base curve chart tends to stay flat as you get into the higher plus powers. This makes the Autograph 2 bi-convex in the reading area. I noticed this a few weeks ago and wondered if it would be a problem. Because the entire power is placed on the backside of the lens of an Autograph 2, I have always believed that the add should be considered when selecting the base curve.
The Seiko Surmount has an enormous intermediate zone, the widest I have seen. its narrower in the reading, but there is a WS version for a wider reading area if you need wide reading too. Since the geometry is reversed, it may take a day or two extra for a prev progressive wearer to adapt, but after that it could blow your patient away IMHO.
I have not tried the Summit Pro, but Hoya lenses generally have a wide intermediate as well, but with much narrower distance than the Surmount.
My Lab told me that they use a Seiko BP design and a shamir SOL design, never heard the terms before, what lens is that?
do any one of you now that ?
best regards
Peter
We use the Shamir Auto II quite often. We have found that fitting at lower pupil margin, especially in higher powers to be most beneficial. When fit traditionally at mid pupil, we hear complaints of noticing the unwanted astigmatism at distance even in moderate powers, which compounds with high powers. This adjustment of lowering the MRP to lower pupil seems to help. We almost never refit out of an Auto II. We also use HR, Trivex, or Hi Index and stay away from Poly at all costs.
Also, are you properly fitting the frame and then sending that frame to be fitted with lenses? This also helps as we see far less complaints complete jobs than with lens only trace jobs.
Hope this helps.
"Strictly speaking, there are no enlightened beings; only enlightened activity." -Shunryu Suzuki
Is the Seiko Surmount better only for hyperopes, or for myopes and hyperopes?
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