3 Nov
2010
3 Nov
'10
7:12 a.m.
Starting to reeducate myself RE astrophotography and have a couple of questions: What should my individual images for stacking look like? I know stacking increases S/N. Assuming typical suburban light pollution, at say ISO 800 what is a typical exposure for eg M27, or M8 with f4 optics? How light/dark should the background be, i.e. how much skylight can I tolerate and subsequently "remove" by stacking? Confirm that for auto-tracking a short FL refractor is better than a longer FL one. The Solitaire tracker has trouble finding a suitable star, say near M27, with my f9 85mm refractor. Thanks for any help. Steve