We can leave this open for tutorial links and people can add useful sites under replies. Maybe give a brief description first then the link to make it easier to reference.
An excellent source of information on exposure time and integration time can be found here. Plan to read it several times to understand but it is well worth it. http://www.samirkharusi.net/sub-exposures.html
Marc Basti
http://www.caelumobservatory.com/video/dvd.shtml
Jan 22, 2011
Steve Coates
http://www.amazon.com/Photoshop-Astronomy-R-Scott-Ireland/dp/094339...
Jan 24, 2011
Steve Coates
http://www.samirkharusi.net/sub-exposures.html
Jan 27, 2011