This is the second deep sky image that turned out okay, and the first Galaxy I've attempted. This time I can tell I achieved a slightly better focus than the Orion Nebula using the Bahtinov mask. I also used a slightly narrower aperture to see if I can reduce the flare of the stars on the outsides of the image, and a higher ISO to give me more adjustment after stacking. Previously I used f/6.3 at ISO-800, and this time I used f/8 at ISO-2000. f/8 appears to have given me slightly less of the flare on the stars, but gathered a lot less light than f/6.3. So much less, that even with the higher ISO and double the exposure time, I had less light to work with. Some of that may be because the Andromeda Galaxy isn't as bright as the Orion Nebula.
The next clear night I get, I'd like to try this one again. It will be easier to see the relative change if I use the same target, plus I'd like to get a better picture of this galaxy. I don't think the narrower aperture did much for the sharpness, so I'll split the difference next time at f/7.1.
Thanks
@Mr. Ashley McGlone and
@Rishi for the pointers and encouragement!
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