So I had some time this morning before work and I went to take a few shots of Orion. Took about 20 six second exposures with my kit lens before I was pushing time. Downloaded them on the computer and found only 5 that were useable for stacking and ultimately stacked only 4. Note to self: Must get a new tripod as my camera kept shifting. Stacked them and was generally pleased, but still feel like I'm missing out on a LOT of detail. What can I do to push the limits of getting detail out of short unguided exposures? I'm guessing lots and lots of images to stack, but doesn't it eventually lighten up the stars and blow them out? Do I need to take equal numbers of dark and flat frames as well even in constellation photos and stack them with it?
Here is my second feeble attempt at astrophotography with my 40D.

), is taking several shots and making a mosaic of them all.
