Stock 11 is a class IV 2 p open cluster located in Cassiopeia. The cluster is the small grouping of stars at the right center of the image. My planetarium program seemed to indicate that it was the grouping at the center of the image but simbad shows no clusters at that location. 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) or here - http://adsbit.harvard.edu//full/2001JRASC..95..194M/0000196.000.html.
Luminance – 15x600s – 150 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
270 minutes total exposure – 4 hours 30 minutes
Imaged from Dardenne Prairie, Missouri (a red zone) on July 9th, 12th, 20th and 21st, 2018 with a SBIG ST-8300M on an Astro-Tech AT90EDT at f/6.7 603mm.
LRGB - https://www.flickr.com/photos/dcrowson/43596666401/sizes/l
My other images of Stock Open Clusters can be found here - https://www.flickr.com/photos/dcrowson/albums/72157689344944815.