What to do before taking images of Jupiter at about 10pm? It gets dark here at about 5pm so there’s plenty of time! I currently have my little Pentax 75mm APO mounted side-by-side with my C11 so that I can switch easily from Deep-Sky imaging to Jupiter and back again.
So, last night I decided to use a H-alpha filter on a target I’ve never tried before – The Gamma Cas Nebula (IC 59/63). Gamma Cas is the middle star of the ‘W’ shape of the constellation of Cassiopeia. The star itself is an ‘eruptive’ variable and its brightess varies from about +1.6 to around +3.0. The nebula nearby the star is quite faint and I used 30 minute exposures; 8 in all making 4 hours of total exposure. The scale of this image (using an ATIK 383L CCD camera) is about 124′ x 92′ (for scale, the Moon is about 30′ (arc-minutes) across. I guess I need to grab some RGB colour soon! Click the image to see the full size version (actually it’s 50% of the original).