Astrophotography Report 9/17/14

So after days and days of nothing but rain and clouds we had a partly cloudy night. There was still a fair amount of cloud cover but it has been far too long, so I ventured out. I am glad I did because the area of interest was fairly free of clouds. At least at first. After I set up, aligned and verified I was pointing at what I wanted to be pointing at a HUGE thick cloud band rolled over. Just my luck. I sat on my hands for a little while until the cloud left. My plan was to give M20 another shot. Well, from my backyard there is a school and a rec center maybe 200,300 yards away. Tonight they have a football game and thus have the area very well lighted. I was unable to find M20. Maybe my alignment was off, maybe I have no idea what I am doing, but I couldn’t see the nebula at all. I scanned around and still couldn’t find it. I looked to see what else was close by and remembered M8 is right there. So I punched in M008 to the Nexstar and there at the bottom of the FOV with my 40mm eyepiece was the faint nebula. I put it in the center of the eyepiece, removed the visual backing, attached the focal reducer, the 2 ring adapter and my T3i. A few test shots and minor adjustments to center everything. Tonight I was attempting to run the camera with my MacBook. Being a Mac guy means I have fewer options with astronomy programs. Apparently being an astronomy nerd lends itself quite well to being a PC geek as well. There are some great programs for PC for astronomy and astrophotography. But I have no interest in buying a PC, and I am reluctant to run windows on my Mac. A program I talked about before called Nebulosity has the ability to capture frames in addition to stacking and processing the frames. I did a quick test of the capturing feature. It worked well and was easier than the stock EOS program that came with my camera. Sadly, as I haven’t paid for the program yet it put lines through each frame as it does with the finished picture. I opted to avoid this incase I use another stacking program, at least my frames will be unmarked.
After the frustration of not finding M20 and the cloud, I finally started capturing frames. I started with M8. After 30 light frames I decided to try for a globular cluster. But which one? Well, what better than the first one I ever saw? M13! I took the T adapter and camera off because I wasn’t sure if they would clear the mount as M13 is fairly high in the sky. I punched it in and the telescope slewed over to M13. I tossed in an eyepiece, centered it and reattached the camera. A few test shots and it was clear that with the lousy tracking with the Nexstar wasn’t going to allow long exposures. I experimented with exposure time and ISO and ended up with moderately decent image. So I captured 20 light frames, 5 dark frames. As before I had poor outcome with the dark frames. I am thinking the main problem is the low amount of data I am getting. With longer exposures and more frames I suspect I will have a higher level of data and then the dark frames will be less likely to darken down the image beyond the point of being able to see any of the detail.
I didn’t spend much time processing these images. But here is M8 and M13.



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