Wide field Cassiopeia

NGC7538 . M52 and NGC7635 the Bubble nebula . Cassiopeia is a wonderful region of the night sky and using a shorter focal lenght telescope reveals its glory. The exposure time was two hours in H-alpha and twenty minutes using each RGB filter . Taken using a 4 inch F7 refractor with the addition of a field flattener making it F6.3:

Here labels are given to identify the major objects in the image: