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M42 Ha/OIII extraction issues
i have a strange issue which i don't know how to correct. I have a set of Optolong L-enhance filter subs shot with an ASI 294mc pro. It's M42 with different exposure times (1sec, 10sec, 30sec, 60sec, 120sec) all during the same session. All subs have been calibrated with flats, darks, bias and BPM. if i look at the separate calibrated subs they look normal, however when i try to integrate them with the HaOIII- extract Ha (or OIII) i get a strange result. I used dynamic distortion and MBB 7%, used 80% of the subs integrated with weight at quality. 1st degree LNC, 3 iter. What did i do wrong? If i leave out the 1sec subs it works fine, however the core will be over exposed then. Attached screenshots of the calibrated subs and the final result in APP.....
Well, that's an interesting result. It looks like the registration is going wrong here and you're telling me that without 1sec, the final stack looks ok right? That might indicate that APP is seeing some of the noise as stars, maybe or is not able to process it well for distortion correction. Could you try without correction?
It may be that the 1 sec frame has too much noise in this case. If you can also try this with 1.076 which will come out as a beta soon, that would be great. It has an improved registration engine.
Vincent, i’ll try that somewhere this week when i’m at my laptop again. I will keep the data set to try 1.076 for sure! Would be nice if that version is able to work through/with this data. I’ll let you know the results here.
I ran the data again without distortion correction and it worked fine. Unfortunately with the 1 sec subs added, the core is still overexposed, but i'll add more short exposures once we finally get rid of the everlasting clouds…..