Stock 12 is a class IV 2 p open cluster located approximately 1,200 light-years away in Cassiopeia. This is one of 24 open clusters compiled by Jurgen Stock in the 1950s. A full list can be found here - http://www.deepskypedia.com/wiki/List:Stock (when and if the reference comes back online).
Luminance – 12x600s – 120 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
240 minutes total exposure – 4 hours
Imaged from Dardenne Prairie, Missouri (a red zone) on August 22, 2017 with a SBIG ST-8300M on an Astro-Tech AT90EDT at f/6.7 603mm.
LRGB - https://www.flickr.com/photos/dcrowson/36642050831/sizes/l