This is NGC281, a bright emission nebula in the northern constellation of Cassiopeia, part of the Milky Way’s Perseus Spiral Arm. It is also called the Pacman Nebula. This is 44 separate images stacked together using Pixinsight. There are 3 5 minute exposure frames, 10 4 minute exposures, 10 3 minute exposures and 21 2 minute exposures. giving a just under 3 hours of exposure. I was expecting another 3 hours of exposure but someone forgot to click start capture at 2 am after the meridian flip. I guess I was tired. Considering the recommended exposure for this nebula is 5 hours of 5 minute exposures. I think it came out pretty good.
This image was taken with a Celestron 9.25 telescope, using a ZWO ASI2600MC Pro, a Antlia Triband RGB Ultra Filter on an AVX Mount being guided by a Celestron Starsense Autoguider. After working through a few guiding issues, I started this image around 12am. At 5 minutes, I had very slight star trails, so I dropped the exposure to 4 minute subs. I got about 10 frames in and bouncy blury stars started in… I changed the Exposure to 3 mins. And then set to 2 minutes before going to be. If all went well I would have had 5 hours of exposure. If I only clicked start capture before falling asleep.
