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Old 17-04-2013, 09:50 AM
Wavytone
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Wavytone is offline
 
Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
Quote:
Originally Posted by Satchmo View Post
an 8" F4 scope with half the pupil admitted is actually behaving as an 4" F8 - so you would expect some increase in edge sharpness despite the very large pupil coming from the eyepiece.
... and a big black blob floating in the middle which is the shadow of the secondary mirror, out-of-focus.
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