Sharpless 180 is the larger emission nebula on the left side of the image. It is located approximately 20,000 light-years away in Cassiopeia.
Ha – 20x1800s – 600 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
720 minutes total exposure – 12 hours
Imaged from Dardenne Prairie, Missouri (a red zone) on August 8th, October 7th and November 8th and 9th, 2017 with a SBIG ST-8300M on an Astro-Tech AT90EDT at f/6.7 603mm.
HaRGB - https://www.flickr.com/photos/dcrowson/43196359105/sizes/l