Binning / resolution question
Silly question;
if you use, say a 2x barlow, and then bin the resulting image 2x2, do you end up with the same thing as if you'd just cropped to 50% in post, or are there appreciable differences?
Presumably, the image that was captured while visually magnified would have less noise due to binning and possibly better guiding than the one that was magnified in post (plus longer subs, I suppose).
If you were undersampling to begin with, I assume you'd get rounder stars with the barlowed/binned version.
If the sampling was good for the seeing conditions and the barlow pushes you into oversampling, then I imagine there would be no visually discernible difference other than noise, possibly guiding quality, with the caveat of longer subs.
Do I have that right?
Apologies for Televue enthusiasts - I know a powermate isn't 'just' a barlow, but 'powermate' is such a stupid name and makes my sentences clunky.
Markus
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