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Old 03-06-2016, 12:01 PM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
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Quote:
Originally Posted by Slawomir View Post

large aperture scope is more capable of producing tight stars than a telescope with small aperture.

(not to mention that large telescope and large camera will be sitting on a well behaving mount, unlike most of small scopes with small CCDs). I believe this might be the main reason for nicer looking stars from large CCDs.
My understanding is that, once scopes get above about 200mm in Australian conditions, the atmosphere alone determines how tight the stars are, with the exception of the few very bright stars, where the diffraction/seeing skirt is tighter with larger scopes. However, in Australian seeing, the resolution of things such as galaxies etc will be pretty much the same for scopes of 200mm and up - a 200mm scope will do just as well as the AAT in resolving galaxy detail.

the above profiles take no account of mount performance, but this will have the effect of increasing the profile width for the best resolving setups, but not affecting lesser ones as much (if they already have broader profiles). So maybe mount noise will even the field the bit.

Last edited by Shiraz; 03-06-2016 at 02:43 PM.
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