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Old 10-02-2015, 11:07 AM
clive milne
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clive milne is offline
 
Join Date: May 2011
Location: Freo WA
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Quote:
Originally Posted by Shiraz View Post
three points should do the job.

For an imaging system (not for visual though), with a 10 inch mirror you really don't need to be too concerned with slight distortion of the optics - you will rarely get better than 2 arcsec FWHM seeing and even slightly imperfect optics can do much better than that (eg 1/3 wave optics is going to be indistinguishable from perfect optics most of the time).
What Ray is saying is essentially correct. In the interests of completeness, however, it should also be pointed out that in a typical imaging rig the ccd under samples the focal plane to a large extent. You would need to be operating at something like f/24 and have perfect seeing before >1/4 wave optics became a major concern whilst imaging.

best,
c
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