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Re: Urban Fables: Stellar by Sunlight



Gary Turner wrote:
Incidentally, I have been told that squinting helps seeing because
it restricts the entering light - causing the pupils to dilate and
improving the available resolution. Is there any truth to this?

I don't believe it has anything to do with dilating the pupils. When
you squint, your eyelids and lashes cover most of the pupil; so it
doesn't matter whether the pupil is dilated or not.

I've always thought that squinting lets the lids and lashes form
essentially "pinholes", which produces an image on the retina much as a
pinhole camera produces an image on a piece of film no matter how long
or short the camera box. The smaller the pinhole, the better the
resolution of the image. I'm ready and waiting to be educated by
someone who can point out where I have gone wrong.

Best wishes,

Larry

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Larry Cartwright <exit60@cablespeed.com>
Retired (June 2001) Physics Teacher
Charlotte MI 48813 USA
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