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Old 22-04-2021, 08:59 AM
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alpal
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Join Date: Jan 2012
Location: Melbourne
Posts: 3,602
Quote:
Originally Posted by Emuhead View Post
should I be realistic and just be content with detail at 1200mm or less?

Yes you should.
The detail is decided by the aperture but
is in practical terms controlled by "the seeing".
Your 200mm aperture is giving you a Rayleigh Limit of .69 arc seconds.
https://astronomy.tools/calculators/...e_capabilities
I know that in Melbourne the best seeing I ever measured -
by using the FWHM of stars was 2.8 arc seconds.
That is well short of the 0.69 arc seconds capability of your scope.
So - we are limited by seeing not by focal length.


cheers
Allan
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