If there are any Nebulosity users out there (and I'm sure there are a few) here's a quick tip to match your exposures exactly across multiple imaging sessions. Got that tip from the Yahoo group
. Nebulosity allows you to place markers on the screen when you load a frame (red, green and blue). By loading one sub (or the stacked channel) of your last imaging session and placing the markers on bright stars you can then go in frame and focus mode to slew and center the image by matching the stars with the three markers. Too easy
