Thanks all for the helpful & informative responses with calculators & examples too. Much appreciated. I've only now got more questions though.
Andy I checked out both of the astrophotographers noted and their work is very impressive indeed. I don't think I'll have the patience that Discoduck has though (50hrs), and I'm not game like Kosborne to go a 10" mirror on an eq6r pro, at least not yet while im still playing nice with the mount.
Where does that leave me in terms of going deeper and getting the most detail possible.. 8" f5, or maybe even the elongated 8" f6, which is where the next question comes in..
3 scopes:
8" f4, 8" f5, 8" f6.
Given aperture determines resolution.. do they all provide the same level of detail ultimately? That is assuming the sensors pixel scale stays between 1 & 2 arc sec/pixel via binning & drizzling where needed, and just imaging longer on the slow scope vs the fast scope to ensure the overall SNR remains consistent across all 3. If I did all that, once in post if i cropped all 3 images to the same FOV would they all basically look identical or would there be more fine details on the f6 vs f4 image?
(Last question: Or based on actual experience with scope types, do refractors arguably provide the sharpest detail available and should I head in that direction..?)