Andromeda Galaxy

Messier 31, the Andromeda Galaxy
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Exposure: 18x90+8x45+8x20+8x10@ISO1600
Telescope: AT72EDII
FF/Reducer:  ATR8 (f/4.8)
Mount: Vixen Super Polaris
Camera: Canon EOS Rebel T3
Processing: Deep Sky Stacker, Photoshop CS6

As I've noted before, sometimes imaging sessions don't work out as planned. Technical problems, the limitations of the equipment, and sometimes just plain incompetence cause problems that create useless or sub-par data.

I had one of those cases a few nights ago.

My intended target was Messier 31, the Andromeda Galaxy. It was a little east of zenith when I started. As usual, my imaging time was short. That, and the fact that I cannot perform a reliable meridian flip with my rig (and I don't have software that can fix the image rotation), led me to decide to attempt to point the scope for imaging on the western half of the sky.

The scope barely cleared the side of the mount.

My first test image had some star trailing, but I assumed that it was the normal periodic error. Alignment seemed to have gone well, so I had no reason to suspect any problems.

The next several images had star trailing, too. Maybe it's the balance in this position, I thought. No problem, I tested the balance when it's pointed further west, so it will eventually settle itself out.

But the images never improved.

Time was running out. I decided that the best way to salvage the session was to shorten the exposure time. That yielded enough usable subs to produce the image above.

Still, I think it is my best image of the Andromeda Galaxy, yet. Did I mention that I'm really impressed with this little scope?