Why does squinting help you see better when you don’t have your glasses on, but doesn’t overcorrect when you do?

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From a previous ELI5, I know that squinting helps you see better because you flex your cornea which helps bend the light to get a better focal point, but shouldn’t squinting when you have your glasses on/contacts in cause an overcorrection as if you are wearing an overprescribed pair of glasses/contacts?

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Anonymous 0 Comments

I assume it’s for the same reasons we can do a camera obscura

[Here is the video](https://www.youtube.com/watch?v=qIp9kItDUh8) by Physics Girl about the Pinhole Camera/ Camera Obscura.
And here is the[same video but skipped to the explanation](https://youtu.be/qIp9kItDUh8?t=232).

Basically when the hole letting the light in is wide open, it is taking in light/images from every possible angle. When the whole closes more, it sorta acts as a filter by limiting the angles that these “beams” of light can come in at to hit any given point. The more closed a hole is, the less beams of light from different angles will hit any given location of your retina, sorta focusing your image.
I never learned this directly, so take my explanation with a grain of salt.. but totally watch the video anyway cuz i think they’re fun

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