I beg to differ... I've seen the results of shooting IC434 through a C11 with a QHY8 @ F/10 and at F/6.3... 10 minute exposures struggle to bring out the fainter nebulosity, I've seen 30second subs of IC434 through a C11 with Hyperstar and the results are amazing...
This is however, a conversation for another thread rather than trashing up Toms thread...
Quote:
Originally Posted by sjastro
It doesn't matter.
For equivalent CCD or CMOS exposures, the number of photons collected is dependent on the diameter of the mirror (or lens). Unlike stopping down a camera lens, you are using the same diameter mirror in which case you won't be going any deeper using the optical system at f/2.
Note the principle doesn't apply to photographic emulsions.
Regards
Steven
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