Thanks for the constructive comments Greg, I do have the AP .75 reducer which is very effective with the RCOS but I want to perfect the guiding at longer focal lengths. Next step undoubtedly will have to be a look at getting an AO8 or similar to try to reduce the impacts of the atmosphere.
I'm quite happy with the RCOS/ST8XME combination. I do have a Takahashi TSA102 which I need to press into service.
I suspect that one of my issues is the lack of a calibrated monitor. On nearly every monitor I put my images on they appear slightly different. I'm going to have to invest in a calibration unit for sure. Having said that, I've noticed a trend bluifying (is that a word) the spiral arms of galaxies and whilst they are aesthetically pleasing, I wonder if we are not making them too blue?
I frankly dont know
Cheers Lars