Have been experimenting with my SW120 achro refractor to see what it can do deep sky wise. It makes a beautiful comet scope, but I also wanted to see if I could shoot other stuff without being blinded by CA. I probably wouldn't bother if I had a nice 4 or 5" ED refractor, but I don't.
Anyway, the Prawn nebula IC4628 and cluster NCG6231 are about 2 hours worth of data. Filters used for this shot are Astronomik CLS and Baader semi-apo stacked. I used the baader primarily to clip some blue that the CLS lets through. 3 minute subs at ISO 1600 were used.
NGC6357 the war and peace nebula was a difficult object. I found it much dimmer than the prawn and my ancient unmodified Pentax K-x was struggling with it. Total data time would be about 5 hours worth. 1.5 hours was with a 30nm bandwidth Ha filter with moonlight present, the rest with a CLS and semi-apo stack. 3 minute subs at ISO 1600 again.
NGC5128 Centaurus A was only 22 minutes worth before the clouds rolled in. It's been overcast ever since. The only filter used was a Baader semi-apo filter. 2 minute subs at ISO 800 used for this one.
All shots were manually guided on a HEQ5 pro.
DSS for stacking, CA reduction and general processing in CS9.
I'm a little disappointed with the star colour in the nebula pics. They are fairly bland. I guess the nebula filters murdered a bit too much colour. For future experiments I will try some RGB filters to try and restore a bit more colour. This way I can focus each channel separately which will also reduce CA.
