We have a patient who's essentially plano with full add who want's sunny PALs...
...the optician thought the frame was flat enough to use a traditionally-surfaced...
...I think it's a little too wrappy (like, 15 degrees) and I like wrap compensated...
...but we don't want to re-bill him...
What's a good, economical option? There are house brand digital POWs, but some are not wrap compensated?
Well, Opticampus calc says a Plano with 10 degree panto and 15 degree wrap is comped zero.
The power might be, but not the off axis performance.
Use an IOT design. They do some very affordable lenses which factor in POW
Gracie
Yep, you could grind -.04 at 180....Originally Posted by Robert_S
What is "essentially plano"?
Your lab may carry this: https://crossbowsoptical.com/products/custom-sport/ . I haven't ordered this wrap design yet, but I have used other Crossbows designs. I can get Crossbows products at Cherry Optical Lab in Green Bay, WI.
I understand that there are certain lenses specifically made to be utilized for wraps, but you should be able to have your lab run compensated specs for any lens- I did when I ran a conventional surfacing lab; you'd think a digital lab could do it just as easily.
Have I told you today how much I hate poly?
I thought (please correct me) that you could either compensate one power or the other but not all in a PAL.
So, maybe you don't have much going on in the distance (the job is like, +0.50-0.25 in one, maybe +0.25-0.25 in the other) but the near zone and the intermediate teeny neck zone are going to need differential compensation.
In other words, you can't use the wrap compensation calculator for one part of the PAL and have it work for all parts. It has to be compensated point-by-point.
I could be completely wrong on that.
But the main concern I have is that bending a +2.25 PAL makes the near zone too skinny and unusable. I think I'm right on that. The designs that adjust for wrap compensation use all their ray-tracing brilliance to re-design the lens degree by degree.
I think.
For very cheaper digital design I do not know for sure.The designs that adjust for wrap compensation use all their ray-tracing brilliance to re-design the lens degree by degree.
I think.
I'm not clear if you have a high base curve (+8 0r +9) in addition to dihedral angle - maybe you don't need to wrap as much if using a high bc.
DRK, I think you are right. I wasn't thinking in terms of trying to comp for near opposed to distance. Do they use their full reading in their suns? ADD could also be lowered if you are looking for them to be able to see their dashboard but not read a book and get you a wider channel as well? From my understanding, it makes a bigger difference in conventional processing.
Have I told you today how much I hate poly?
Reducing the add for near working distance does not work in a PAL, FT only.
Most people will be fine in that Rx in a 15 degree wrap that is not compensated. Maui Jim used younger image for years and years...
Most POW compensated lenses are just going to tweak the power based on angle, they're not going to do any re-design to account for high wrap. That's what the wrap designs specifically address, in addition to the rx compensation. My go-tos, though not particularly cheap, are Auto 2 Attitude and Essilor Ideal Advanced Wrap. Most house digitals, like IOT, should have a dedicated wrap compensated design as well. But I agree with others in this Rx and moderate wrap I think it's unnecessary. As ak47 mentioned the good old King of Wrap Younger Image would address the wrap issues at a very good price point. I routinely put stronger Rxs in 6 base 15 degree wraps without compensation and have no issue.
I appreciate the input.
I hope you're wrong, Dan.
My thinking is that a +2.25 add is already narrow enough as to be difficult to get a nice binocular effect when wrapped, which narrows it even further. I'm not sure how they specifically finagle the design when wrapped in order to not make it narrow, but I have a feeling it has to do with giving up a little softness down low (as opposed to adding peripheral blur in the distance portion of a sunglass, which would be unwise). I think that's the ray-tracing at work. I think that's a totally separate issue than power compensation.
Plus there's that slight outset that's needed for a wrap...and even a smidge of BI prism...
As to total power in the near zone, it's not a lot, but it's not plano, either. Sure, the distance zone doesn't need compensated. I could live with the add turning into +1.88-0.27x099, or whatever. That's not the concern I have.
I would expect all of the above in a high-end PAL design. Maybe you're right, though, about the lesser-sophisticated designs (you know, the cheap ones!) not taking all that into account.
I would love to expect that too. You'd think the most customizable lenses would vary every conceivable factor based of POW. But all the designers have different (and less expensive) product for wrap lenses. Autograph Intelligence is not recommended for wraps, the Attitude designs are. Essilor has the basic Ideal, Ideal Advanced, and finally the Advanced Wrap. We are even dissuaded from using the hoity-toity Varilux X Series for wraps, they have the less expensive Stylistic, Zeiss has a Sport wrap lens. Perhaps it's just marketing and I'm falling for it, but why would they make and recommend lower-tier product if the top-tier could do it as well or better? As you said there are unique design compensations required for high wrap, and I think the top-tier products just aren't designed with that intent and don't accommodate it.
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