The Cave Nebula cataloged as Sh 2-155 and Caldwell 9 is in the constillation Cepheus at about RA22hrs 57mins DEC62deg 38mon.
This image is about a 1X1.5 degree crop from the origional with celestial north up and east left.
The red color is from glowing Ha gas, the blue is from reflection off of dust and there appears to be some O3 and Hb in the central part.
The dard areas are clouds of dust in our own Milky Way.