I assumed he’d estimated it based on how distorted the face appears behind the glasses. I do that all the time.
At this angle it’s hard for me to do that, since I usually use the edges of the face to estimate it. negative glasses pull the line inwards, positive outwards. I can reliably tell when someone is wearing fake glasses (0 strength) for example, and probably estimate strength within 30% of the actual value.
If the image was higher res maybe I could estimate this case too. Or this professional optometrist is just a lot better at it than I am.
Strong negative glasses: (Note the faces contours in the glasses appearing well inside the faces contours around the glassed)
Fake glasses:
Positive glasses:
PS: Searching for generic terms yields 100% fake glasses, so I took a specific person I remember having strong glasses for myopia.
Going for “I see you” with a plausible but bullshit unit name but yours works too. Maybe they keep getting into accidents and landing in the ICU because of poor eyesight.
Might depend on the material. I have -3.5dpt on both sides and my glasses have half the width and glare. Or are those some random units again?
I assumed he’d estimated it based on how distorted the face appears behind the glasses. I do that all the time.
At this angle it’s hard for me to do that, since I usually use the edges of the face to estimate it. negative glasses pull the line inwards, positive outwards. I can reliably tell when someone is wearing fake glasses (0 strength) for example, and probably estimate strength within 30% of the actual value.
If the image was higher res maybe I could estimate this case too. Or this professional optometrist is just a lot better at it than I am.
Strong negative glasses: (Note the faces contours in the glasses appearing well inside the faces contours around the glassed)
Fake glasses:
Positive glasses:
PS: Searching for generic terms yields 100% fake glasses, so I took a specific person I remember having strong glasses for myopia.
Just looked in the mirror… Checks out! :)
Thanks for the explanation. And yeah, on the op picture you can’t see any of that clearly, so he needs to have serious practice for that statement.
I’m sure Jonathan was able to provide the exact prescription at a glance.
It’s measuring in Imperial Corrective Units (ICU).
Let me guess… It counts how many visits to the ICU it took to get such bad eye sight?
Going for “I see you” with a plausible but bullshit unit name but yours works too. Maybe they keep getting into accidents and landing in the ICU because of poor eyesight.
Aaah… So ist not the original prescription, rather the hit count. Like snipers carve lines in their rifle.
Now it all comes together!