Sharpless 104 (LBN 195, DWB 14 (http://adsabs.harvard.edu/full/1969A%26A.....1..270D) and others) is a bright, circular emission nebula approximately 13,000 light-years away in Cygnus. The stars ‘in’ the nebula are cataloged as open cluster Dolidze 4.
Ha – 24x1800s – 720 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
840 minutes total exposure – 14 hours
Imaged over seven nights in September and October, 2018 at Dark Sky New Mexico at Rancho Hidalgo (Animas, New Mexico) with a SBIG STF-8300M on an Astro-Tech AT12RCT at f/8 2432mm.
HaRGB - https://www.flickr.com/photos/dcrowson/44863369284/sizes/l
See my much wider view taken with a refractor here - https://www.flickr.com/photos/dcrowson/30565417537.