Hello,
since some time I noticed some kind of "centered color gradient" in all my RGB's (greenish in center, reddish around) which I don't understand because I use this equipment since years without a this effect. This is seen in now in al RBG's doesn't matter in which sky region or climatically conditions. (see attached pic, just calibrated and basic stretch)
OFC This has nothing to do with PI but since here are a lot of experienced specialists maybe someone knows what could cause this.
What changed in my setup since I noticed this behavior was:
- I installed my setup on a dark sky remote place.
- I had to do an "anti-banding" Firmware update on my QSI 683 camera / Astrodon filter.
- I cleaned the front lens of my Tak FSQ 106ED with Baader optical wonder Cleaning Fluid.
(I am not making any of this responsible, it is just for information)
What I have tried so far.
-I made fresh BIAS/ DARKS / Flats library , tried it with 2 different flat field panels , and tried it with different flat ADU values : ~ 23.000 / ~ 35.700
- Even if I calibrate the RGB's without flat's the "centered color gradient" is visible.
Info:
I am doing RGB at 1:1:1 exposure length at -20°C
I activate a dew heater if humidity goes above a certain level. (> 80% RH)
I doubt it's caused from light pollution since all RGB's showing a "centered color gradient".
PS: Primarily I am not asking how to solve this with a tool like DBE or others (though it could be a pain) , I just want to figure out what is causing this since I didn't had this in the past with the same equipment.
Any help is welcome.
