Track with me on this one:
I wear contacts and see a blurry cluster of shit if I don't have them in. If someone was filming something and put my contact lens in front of the camera lens and then imported the footage, would it look clear to me and blurry to other people? I always take for granted that a movie looks the same to everyone, but if it is filmed with a glass sheet in front of it with a prescription for vision, would that changes things? I'm sure there's an elementary answer to this, but for some reason I've pondered it a lot.
no, it would just look blurrier.
glasses/contacts work by bending rays of light passing through them, and effectively modifying the light's focal length so it falls onto the retina inside your eye. Think of the retina as a screen in a movie theatre - if the projector isn't focused right, it will look blurry.
Short-sightedness is caused because the eye's focal length is in front of the retina (i.e. the focusing point ends up short), and is corrected by having light bent outward to correct it through a concave lens (see diagram below):
Long-sightedness is the opposite - where the focal length falls beyond the retina, and is corrected via a convex lens which bends the light in even further
if you filmed with an hypothetical contact lens over a video camera, all you would get is an out of focus image. Which if you're watching it without any further optical aids, will be even blurrier.