In betwen the clouds (suckers gaps!) have been experimenting with ICNR vs darks and have found (in my case, probably due to lack of skill in processing and temp variations) the ICNR to be far better. I found with IP and separate darks my images would have diagonal streaks visible if pushed hard, these are due to warm and hot pixels and I think it may be fixed by using adaptive darks and median rather than average for dark processing...more experiments and reading are in order, anyway this image was taken before the clouds rolled in - again...
This is through a 50mm Pentax SMC lens on the Canon 20d, iso 400, 120s. I have really had to fight to get the light pollution out and the colours back to some semblance of reality. Not a great shot but for now it's all I've got
