I’ve been doing astrophotography for about a year. This weekend, I started working on a recent capture of the Rosette nebula. After stacking and color calibrating, there is significant pink fringing that I haven’t seen in the past. I’m assuming this is an issue with flats. My flats were taken in aperture mode (so the camera selected the shutter speed) at the same ISO, focus, and focal length. Hoping someone can help me learn what’s going on. I’ve included a picture of the stacked, color calibrated, cropped image, along with one of the flats. Thanks for the insight!
Hello, this looks like an over-correction of flats, for which a detailed explanation can be found here: Siril - Synthetic biases
In case you’re processing manually, don’t forget to check the equalize CFA box at preprocessing time.
Thanks - I’m using the OSC_Preprocessing script. I tried some of the adjustments described in the “Siri - Synthetic biases” link you posted, but I didn’t see a change. (There’s a good chance I did it wrong.) I am wondering if the “OSC_Preprocessing_withbackgroundextraction.ssf” or “OSC_Preprocessing_WithoutFlat.ssf”, but I’m not clear on how to install a script. Can you help?
Using a script is described here: Siril:scripts - FreeAstro but I guess you already saw this. Put your scripts in a directory of your choice and add the directory to the list in the preferences of siril, it will appear in the list of the top menu.
I don’t know what is wrong with your images. Maybe you can share your flat image, so we can see if it’s correct.
