Dave,
I processed my images as jpegs due to file size. So image does suffer from multiple process jpeg blocking as well as star movement and frame registration with my primitive kit. Next opportunity I will try a longer exposure time and stack a lot fewer tiffs.
All down to processing power. 35 light frames + 1 dark as jpeg = 120.24 mb as tiffs this would have been 2519.64mb. Each jpeg run took an hour and a half so I have no idea what a tiff run would take.
All down to Alex now if he has some samples with his new fancy kit.
Don