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Old 13-05-2020, 08:01 PM
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jayconnor (Jay)
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Join Date: Mar 2015
Location: melbourne
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Quote:
Originally Posted by astro744 View Post
Visually f4 is very demanding on eyepieces and you definitely need a coma corrector, (and at f5 if you are picky). However the OP did not ask for a visual recommendation, rather a photographic one. Put simply f4 is faster than f5 and in photography and astrophotography speed is desired, (f2 seems to be a goal of many).

An f4 telescope is photographically faster, is capable of a wider true field for the same aperture, is lighter, but does requires a better structure keep it in collimation. It is perhaps a good choice once some experience is built up with an f5 telescope first. Photographically both require a coma corrector.

I found the following discussion on this forum some years ago. See http://www.iceinspace.com.au/forum/s...ad.php?t=88094

great thread you sent me too. thanks for that mate.
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