Re: [ATM] More on aperture stops

["Jerry" <wa4guu@verizon.net>]

Hello Arjan:

Well ... a smaller eye pupil can make a difference. There is likely to be
more total aberrations (astigmatism and other aberrations) in the dialated
pupil, "full aperture" eyeball. 

The smaller exit pupil that results when the telescope is stopped down could
cause the light bundle entering the eye to miss the more aberrated portions
of the eye's cornea and lens.

You could double the telescopes full aperture power to get about the same
size exit pupil as when stopped down. Or maybe you could look at a brightly
lighted flat field to stop your pupil down just before looking through the
telescope. See if either of these has the same effect as stopping down.
Doubling the power is probably not reasonable. It will probably be too high
power to be reasonable for a 6" except in the best of seeing conditions. 

Jerry





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