NGC 457, also known as the Owl Cluster, is an open star cluster located approximately 8,000 light-years away in Cassiopeia. According to the NGC/IC Project Database, it contains about 150 stars at magnitude 12-15.
NGC 436, at the top right of my image, is another open star cluster located approximately 9,800 light-years away.
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 July 10th and 13th, 2013 and November 11th, 2015 with a SBIG ST-8300M on an Astro-Tech AT90DT at f/6.7 603mm.
Original RGB image from 2013 - https://www.flickr.com/photos/dcrowson/9290366746/sizes/l
New image with Luminance - https://www.flickr.com/photos/dcrowson/22754575455/sizes/l