Quote:
Originally Posted by Shiraz
Not sure Suavi. From reading, SNR of maybe 5 is adequate for the surface brightness fluctuations to be noticeable with a close galaxy - my system will do that quite easily in a few hours with a typical sky. The source papers are a bit heavy for "idle curiosity" reading, but, from a skim over, it seems that the effect is noted in very short (eg 1 minute) images from big scopes at 1 arcsec seeing, so it does not feel like it is stretching thing to assume that we will see similar in multi-hour images at 2 arcseconds. In any event, I started digging around because I ran into "noise" that did not smooth out with more exposure - I now think that I may have already seen this effect on a few galaxy images (this one in particular http://www.astrobin.com/full/276705/0/?real=&mod=). cheers |
I stand corrected. Had no idea about the real magnitude of these variations. Well, in the end I am a narrowband guy
