M51 Pinwheel Galaxy

I finally got fed up with my home made barndoor tracker. It worked most of the time, but it was really sensitive to a lot of factors. One of which was the orientation of the camera. If the camera hung over the hinge the tracking was entirely at the wrong rate, and the hinge itself wasn’t strong enough to handle larger lenses.

I started down a path of fixing these issues but I realized “I don’t want to build trackers, I want to take photos.” One day I might get back to building a better tracker but for now I want to focus on the imagery.

I spent some time patrolling the cloudy nights forums for deals, and in the end I purchased a used Celestron AVX mount and an Astro-Tech AT72ed refractor.

Of course, as soon as the equipment arrived the California drought seemed to end and I was besieged by cloudy/rainy skies most nights for a few months.

Finally I was able to get a few clear nights and I got some practice aligning and taking photos with the mount. There were a lot of moving parts this first night. Backyard EOS, aligning the mount, focusing, etc. So my goal wasn’t a lot of light as much as exploring the equipment.

My first target was M51, the pinwheel galaxy:

Picture saved with settings embedded.
10 subs 60s each @800 ISO

In the end the tracking was ok, but the go-to calibration was way off. I ended up with M51 in the edge of the field of view which led to some distortion.

It was getting late by the time I got everything working, so I stuck with only 10 exposures. I just wanted some time to play around with editing, but 10 minutes of integration time is looking pretty good for a start!

  • 10 x 60s @800ISO
  • 20 Bias
  • 10¬†Darks