A work in progress: As done as it will be for a while: a mosaic of IC1805 and environs. Since the first time I shot this field, I've been entranced by the repeated forms of lacy dark clouds and UV-eroded pillars near the bright cluster. It's an expansive tract of sky. Three fields begin to do it justice:
IC 1805 and environs
~8x900s H-a, ~4x900s O-III, ~4x900s S-II for each panel
(Click the image for a better presentation.)
Hydrogen, oxygen, and sulphur at play out in the wilds of Cassiopeia.