Wikipedia:Reference desk/Archives/Science/2023 May 14

= May 14 =

Odd glasses effect
So I just got new glasses. The prescription seems to be right - because I can actually read what I am typing here. But the shape of anything that is circular, like the top of cup for example, is changed to an upright oval. I have never experienced this before. What is causing this? Will this damage my eyesight? 86.187.236.117 (talk) 09:00, 14 May 2023 (UTC)
 * WP:NOMEDICAL
 * All that can be suggested is reading our existing articles such as Corrective lens, Eyeglass prescription or Astigmatism. Martin of Sheffield (talk) 09:24, 14 May 2023 (UTC)
 * Thanks. Do you know if this topic is mentioned in any of those articles? 86.187.236.117 (talk) 09:26, 14 May 2023 (UTC)
 * I can't say. Read the topics if you want to, but for real advice see an optician. There's no point is asking for more help here, we are not allowed to give any, see the notice above. Martin of Sheffield (talk) 09:56, 14 May 2023 (UTC)
 * "Wikipedia is not an optician". Too bad. I was hoping Jimmy Wales could fit me in for a quick eye test at 9am on Monday. I'm not sure why you are recommending those articles if you don't know what's in them. What if I had framed the question like this: "Sometimes spectacles can distort shapes by making circles appear as ovals. How does this happen?" I thought the answer might be a simple one. But thank you for replying anyway. 86.184.26.97 (talk) 10:20, 14 May 2023 (UTC)
 * Standard prescription eyeglasses, that is, not meant to correct for any other issue than myopia or hyperopia, should not change the subjective experience of the aspect ratio. Look with one eye through one glass at a circle. Rotate your glasses (but not your head). Does the oval rotate with them? Then the effect is due to your glasses. You should refer to either the optometrist who wrote the prescription, or the optician who dispensed your glasses. If the prescription was not intended to also correct for some other issue, something is wrong with the glasses. If the prescription was intended as a correction, it appears to be working; you'll get used to it in a week or so. --Lambiam 11:44, 14 May 2023 (UTC)
 * Yes, the oval rotates if I rotate the glasses. It's not being caused by my eyes, obviously! You mean this distortion is common with glasses that have a new prescription and this will disappear in a week or so? Is that written down in some Wikipedia article? Thanks. 86.184.26.97 (talk) 11:54, 14 May 2023 (UTC)
 * We are urging the OP to consult their optician without knowing whether "just got new glasses" was on personal prescription or by guesswork. A common spherical lens does not change its image distortion when it is rotated. An exception is a progressive or graduated prescription lens whose Optical power varies smoothly from top to bottom. This type of lens distorts strangely when rotated and it is prescribed exclusively for use right-way-up by the one person (often elderly) who was examined by their optician. Human Visual perception is a process that unconsciously corrects for many distortions (including the obvious distortion of the physical image on the retina being upside down) and it is learned over time. This means that a distortion apparent with new spectacles depends on how one previously viewed the world i.e. one can become so habituated to view through a distorting lens that the undistorted view without a lens seems wrong. To the OP: for the advice you seek, please do consult a qualified Optician who will be aware of these factors as they may apply in your case. Philvoids (talk) 13:39, 14 May 2023 (UTC)
 * The general incompetence demonstrated by this particular optician over the previous six months suggests to me that they don't really know what they are doing. Or that they have a very unreliable supplier. They originally offered to re-glaze my expensive titanium Stepper frames and recommended varifocal lenses. Then, after a delay of over two months, they managed to get those frames "lost in the post". When I was able to choose alternative new Stepper frames, the glasses that came back were unusable for working at my computer terminal - there was only a tiny area of adequate magnification right at the bottom of each lens. They offered to "adjust" the fitting - but when they came back again, weeks later, they were just as bad. Having decided to forget about varifocals, they made up single prescription glasses and these now turn circles into ovals. I'll not be going back to that optician again. But thanks again for the advice. And yes, I realise that "Wikipedia is not an agony aunt." 86.184.26.97 (talk) 17:15, 14 May 2023 (UTC)

My question was a genuine one. I wanted to know if the optician was likely to be at fault, or if it is a common phenomenon. I still don't know. But I suspect that there is no answer to that question at Wikipedia. But my question is now labelled as "trolling". I'll ask elsewhere next time. 86.184.26.97 (talk) 17:56, 14 May 2023 (UTC)


 * You're a banned user. Go away. ←Baseball Bugs What's up, Doc? carrots→ 18:12, 14 May 2023 (UTC)