I've been sort of "into" astrophotography from the moment I got a DSLR. I realized that being able to take long exposures would mean I'd be able to take nighttime shots w/ a tripod, so I got myself a hold of a carbon fiber tripod (it's really light; I like taking it along if we go for a hike because it's not too heavy) and did shots beginning with my T2i...
T2i: Not much experience at this point, but I believe this shot was with TheGirlfriend's 15mm f/2.8 Fisheye. I had the camera set to do 10 exposures with a +/- 1/3 EV bracketing, totaling 30 exposures. Set up the camera, hit the remote button, and walked away for 10 minutes. Luckily, one of the shots caught a meteor streaking across the sky. There's a bit of light pollution in the corners, but if you look close enough, you can see the edges of our galaxy (that misty part that looks like a cloud. I assure you it's not a cloud.
Next shot is from my next body, the Canon 6D. This shot was set up on a cold night, so I did a few very high ISO shots to get the framing / exposure right without freezing to death waiting for 15 second exposures. After getting it in high ISO, I used the click-for-click rule (My ISO goes in 1/3 stops on that camera): for every click down in ISO, I slowed the shutter one "click" of the scroll wheel. This is something I've explained before in another article. Took a couple shots, threw a 77mm Purple to clear graduated filter on the 17-40mm f/4L and took a couple final shots and ran back to my car.
The final shot, and the most recent I've posted (although, with the high ISO capability of the 6D and the 85mm f/1.2, I was able to do a hand held shot of Orion since this shot...) is from the Canon 1D Mark II N w/ the 35mm f/2 attached. Settings were 13" | f/2 | ISO 800. Just got home, set up the settings, set the lens to infinity, set the self timer, rolled the window down and set the camera on top of my car facing up. Waited, and voila.
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Overall, I think I think either the 1D is the best for this out of my cameras, or that I've just gotten better at shooting at night... Either way.