Hi Guys
M17 Swan Nebula in HaRGB 13hrs exposure time.
3nm Ha 10hrs (30 off 20min subs bin1); RGB each 1hr ( 6 off 10min subs bin2).
Learnt an interesting thing through hrs of trial and error. I usually use STD sigma data reject in CCD stack (its the 1st on the list, what do I know?), but tried Poisson Sigma on M20, after watching a Guru how-too video. Poisson Sigma is much more agressive and leaves no bad bits. Very smooth and crap free BUT, if your stars are not all near perfect in every sub (eg eggy), it butchers them to hell, and artifacts appear really quickly with deconvolute. STD sigma seems to leave them alone, but some work in PS is required to clean up. Small point you say, but hugely time consuming to trial properly, results can be very different.
Anyway, I think the star thing is slightly better on this one, still working on that, Mike will no dought crucify me again
. And maybe Jase might recommend his lose-the-stars trick, which I will do if he or someone thinks its worth it.
Thanks for looking
