Easing Eye Strain with the Right Lenses (2012)

Re:Easing Eye Strain with the Right Lenses (2012) by jasode on Saturday September 30, 2017 @06:06PM (#15375221)

>I also gave up on progressives and now have two pairs: readers and drivers.

Yes, both progressives and high-index lenses suffer from the same problems: smaller field-of-vision and higher distortion of peripheral vision

If I sit with my eyes 36 inches away from a 30-inch screen...

With a single-vision lens, without my head moving at all, my eyes can move within their sockets to see the bottom corner of screen showing the date & time, and to the top corner showing the [x] button to close windows. Single-vision lenses have edge-to-edge clarity.

With progressives or high-index lenses, it requires rotating & tilting my head to put those corner locations directly in my central field of vision. Imagine a horse with blinkers[1]. The edges of those lenses are blurrier so you have to move your head to move the lens' center spot toward the item of interest for maximum sharpness.

Maximum field-of-vision is the optimal ergonomics of looking at multiple windows of text on a 30" monitor. Yes, high-index lenses are thinner and more fashionable but I don't need that when concentrating on programming code and reading web pages.

>You cannot depend on optometrists+opticians to make the right choice for you. You need to educate yourself on the available choices.

That's why I bought my own set of trial lenses[2]. I can methodically optimize my computer distance vision without exhausting the patience of my optometrist repeatedly asking, "which is better? 1? or 2? (again) 1? or 2?". I then go to Zenni and order the exact diopters I need. (I'm not going to buy a glaucoma tester so I'll still go to the eye doctor for that.)

I end up with 3 separate pairs of single-purpose glasses: 1 for reading books ~12 inches, 1 for computer distance ~36 inches, and 1 for driving 20+ feet. Swapping out glasses for each purpose is inconvenient but the larger field-of-vision makes it worth the hassle.

[1] https://en.wikipedia.org/wiki/Blinkers_(horse_tack)

[2] http://www.ebay.com/sch/i.html?_nkw=trial+lens+set

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Re:Easing Eye Strain with the Right Lenses (2012) by CalChris on Saturday September 30, 2017 @06:45PM (#15375371)

That's a really good description. My TL;DR would have been that everything was bad with progressive lenses. I can drive with my readers and if I slide them down my nose, I can read with my drivers.

I'm lucky I guess. I'm myopic with an FD of about 12 inches. So it was really dumb to have progressives with the near FD set to 12 inches.

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Re:Easing Eye Strain with the Right Lenses (2012) by mixmastamyk on Sunday October 01, 2017 @03:12AM (#15376771)

Thanks, the same happened to me but had no idea what I was doing. Tried the bifocal progressives and the top half was fine but bottom was like looking though coke bottles. Had to move my head constantly to get text centered. Constant movement and fishbowl effect drove me nuts. Thought they were defective.

Returned them for one computer set and one driving (closeup fine) and they work well, but up until now thought they or I did something wrong.

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Re:Easing Eye Strain with the Right Lenses (2012) by jasode on Sunday October 01, 2017 @05:45AM (#15377064)

>but bottom was like looking though coke bottles.

Yes, exactly! Many others have the same issues and describe it in similar ways: "tunnel vision", or "looking through a pinhole"

It's very strange that optometrists & opticians don't explicitly explain this trade-off upfront: the "convenience" of progressive bifocals and the "fashion" of hi-index lenses will always be blurrier away from the center point than single vision lenses. If customers were properly educated ahead of time by the opticians, they wouldn't think progressives and hi-index were "defective". The lenses are not defective -- it's actually an unavoidable optical tradeoff! Your eyes just happen to be sensitive to it.

Some people adjust to progressives or high-index lenses just fine. Others don't. I tried them for 3 weeks as they recommended and never got used to them.

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Re:Easing Eye Strain with the Right Lenses (2012) by mixmastamyk on Sunday October 01, 2017 @01:22PM (#15378779)

Right, for me the sensitivity came from moving between monitors.

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Re:Easing Eye Strain with the Right Lenses (2012) by jeremyw on Sunday October 01, 2017 @05:11PM (#15379829)

Thanks for the tip on cheap trial lens sets. I've been eye hacking with variable lenses, but that tech isn't quite baked yet.

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Re:Easing Eye Strain with the Right Lenses (2012) by lucaspiller on Saturday September 30, 2017 @09:04PM (#15375863)

There’s some good advice on this thread, and I’m definitely going to do some reading before I go to the optician next. I’ve been wearing glasses for 15 years and I don’t think I’ve ever had a pair that are really comfortable for computer work. The best I had was contact lenses, but now I have a weak astigmatism which they can’t correct properly.

Anyway I wanted to ask about your test lens set. Do you just go to the optician with the glasses? I get the impression they’d give a reaction as if you are self diagnosing from something you’ve read online...

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Re:Easing Eye Strain with the Right Lenses (2012) by jasode on Sunday October 01, 2017 @05:50AM (#15377083)

>and I don’t think I’ve ever had a pair that are really comfortable for computer work.

Yes, if your using desktop monitor is 2 or 3 feet away, that's an intermediate distance and neither reading glasses nor driving glasses will provide the optimal sharpness. If your "computer work" is a laptop monitor, a prescription for reading glasses (~12 inches) may also work for that shorter distance.

>Do you just go to the optician with the glasses?

No, I order them online: https://www.google.com/search?q=glasses+online

Those websites let you type in the numerical values for sphere, cylinder, etc. You don't need a prescription. (It's the online contact lens websites that require a faxed prescription or a confirmation phone call with the optometrist.)

If you need a tutorial for how to use a trial lens set, there are lots of youtube videos and text websites explaining SPHERE, CYLINDER, AXIS, ADD, PD, etc. It's really easy.

I used www.zennioptical.com but the others websites have good reviews as well.

If you absolutely must use a local optician such as LensCrafters, EyeMasters, Pearle Vision, Costco, Walmart, etc because you need to try out the frames on your face, a trial lens set isn't going to be as helpful to you.

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Re:Easing Eye Strain with the Right Lenses (2012) by bigjimslade on Saturday September 30, 2017 @09:25PM (#15375919)

But how do you see your dash while driving? Do you just see through the blurry?

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Re:Easing Eye Strain with the Right Lenses (2012) by jasode on Sunday October 01, 2017 @05:54AM (#15377097)

The dash is a little blurry which is acceptable since there's no information that requires sharp vision. If I bought a Tesla where lots of important text is shown on the giant LCD monitor in small fonts, I might have to use progressives.

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