Thanks everyone for the replies.
All my previous work was done with film cameras on a F4.6 newt which of course captures the stuff that IR filters on DSLR's block. I must admit I prefer my film stuff for nebulae, and not just because you get the red, but its just too difficult to process correctly and quickly.
As for Photoshop, the cost is prohibitive. I use DSS for stacking and Gimp for post processing.
I have been practicing polar aligning and tracking so hopefully soon I will be able to do extended exposures.
My other issue is dragging my gear in and out, its heavy and the mozzies are having a field day. I had an observatory set up in my backyard some years ago (Sunbury) and a Newt on a good solid pier till the neighbours Jacaranda grew to about 8 m and completely shielded all the South sky. Then the East and west were blocked by gum trees, so all I have from ground level is NNE to NNW. I am considering making another double story observatory at about roof height and simply operating the scope from my study. For me though it takes away some of the magic. I could of course just chop all the trees down, then I would miss the parrots - some people are never satisfied, insist on cake and eating

Any onwards and upwards (perhaps literally)
Thanks again.