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Old 06-25-2018, 07:27 AM
 
3,608 posts, read 1,533,282 times
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Quote:
Originally Posted by ocpaul20 View Post

I just wonder how animals get by with their eyesight which is more important than ours as they dont have glasses and if they have bad eyesight, they die from starvation.
Poor eyesight is largely inherited. Animals with poor eyesight (for species that rely on it; many animals rely mainly on smell or sound - for example, badgers and bears) die and don't pass on their genes. Humans with poor eyesight haven't been doomed to an early death for tens of thousands of years, ever since the beginnings of civilization allowed specialization of tasks. So, a man with poor eyesight might well have been a toolmaker or something similar.
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Old 07-08-2018, 10:13 AM
 
Location: Maryland
836 posts, read 246,883 times
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Pinholes do not produce very well defined images because of diffraction effects. They just never produce images as good as a quality lens, hence the overwhelming popularity of regular lenses for imaging purposes. It would drive me crazy trying to look through pinhole glasses all the time.

https://www.flickr.com/photos/dominicspics/4589206921/
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Old 07-09-2018, 01:57 PM
 
18,991 posts, read 6,213,032 times
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This therapy was around over 30 yrs ago, I looked at it. I'm 80 now and have been wearing reading and distance lenses all my life and taking quality eye supplements. Never needed cataract surgery either.
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