eli5, how is it that cameras can see clearly underwater whereas human vision gets blurry?

Question

eli5, how is it that cameras can see clearly underwater whereas human vision gets blurry?

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Answer 1

Cameras will not see clearly underwater if the (rounded) lens contacts the water. They will only see clearly if a flat lens protector in front of the lens contacts the water.

Human eyes will not see clearly underwater if the (rounded) eye contacts the water. They will only see clearly if wearing goggles (which need to have a flat front surface).

The shifting of the light happens at the interface between materials. Our eyes evolved to account for bending light from air into our eyeballs. As are most cameras. But, if you have a thin, flat surface, light is not refracted.

This is why all goggles always need to be flat. There would be a substantial lensing effect if they weren’t.

Marine anomals presumably see fuzzily, as well, when not in water.