I took a 5 minutes shot, then a 3 minutes shot, then a 2 minutes shot, then a 1 minute shot then a 30 sec and a 15 sec shot at ISO 400 quickly before the sun rise. Had to image M42 quickly as the sky was blue already.
total time 11 minutes and 45 sec. used layered mask for the core so it doesnt burn out. not that happy with it. Should have started imaging it more sooner.
cheers.