Trev, i have taken some pics of IC4605 the same region in Scorpio, and i was looking at 10 minute subs minimum, for capturing anything to good effect. 20 mins would be better, and easy doable with no noise on the QHY8
ADDENDUM : Mate, i would say the FOV of the RC is way to tight, its too tight even with my 8" F5 scope, and i have found the only half decent way to capture it, is with a Canon lens to QHY8 adaptor, using a 55mm zoomed in.