This is my first time processing deep sky images with flat frames and I am using DeepSkyStacker to stack my light frames and flat frames of Leo Triplet.
But the result image looks very different from what I wanted to get and it seems that flat frames make vignetting even worse and flat frames erased some details from light frames (lightframe-only stack on the right side):
With flat frames: Without flat frames
I used my 16-inch Macbook Pro screen with a pure white background to capture my flat frames (by holding it as close as can to the telescope).
I took flat frames with same focus/temp/gain right after my light frame image session (exposure time 1.4s and 31 flat frames).
I adjusted exposure time several times to move most of the tops to 1/3~1/2 of the histogram graph and below is how my flat's histogram looks:
Here are the stacking params I used:
Could some one help me identify the problem? Thanks in advance!
And could some one tell me why my stacked picture is greenish? I consulted ZWO tech support about the debayer algorithm I should use and I used RGGB in DSS FITS file settings as they suggested.
If I am using the correct debayer algorithm, the resulting color should be more "natural" instead of this weird green, I guess?
Equipments I used:
ASI533 MC Pro
SkyWatcher 150 PDS
Edited by maxhy, 17 May 2021 - 10:30 AM.