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Comment by tenken | Hacker News Reader

And here I thought they meant Eyes Glasses .... Darn.

I also thought they meant eyeglasses. I used glasses for a few years and never cared much for chromatic aberration, but once I started to use contacts, going back to glasses makes it very noticeable, specially on the periphery of the lens. Lenses on glasses need to be very high quality to approach the image quality of contacts in terms of distortion.

Last year I got a new prescription and the optometrist convinced me to switch to higher refractive index lenses, because they are thin, light, don't have a subtle yellow hue like CR-39, don't distort the facial features and so on. I agreed and couldn't wear them at all due to insane chromatic aberration. After a few complaints they relented and replaced the lenses with CR-39 and I have been happy ever since.

Do you mean "High Index" lenses? ... I have strong prescriptions of -9.x and -11.x and I have had 1.66 index lenses. I've always noted to doctors light sources move around or float around alot with the lenses. I haven't necessarily noticed a difference with contacts (but I did see sharper with hard contacts) but my eyes cannot tolerate hard or soft lenses.

I have tried even higher index lenses, but anything above 1.66 and the distortions and optical aberrations get too annoying ...

Yes, high refractive index lenses. -9 and -11 sound like actually good reasons to recommend them, at these levels of myopia lower index glasses should be noticeably heavier.

What I couldn't tolerate was specifically chromatic aberration. Every letter in this text box would have a yellow and blue fringe if my head was turned even slightly. And this would happen with every high-contrast border, like someone's t-shirt, a white car or a house against the sky.

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