Weird blooming on NGC6188 OSC image

[RugbyRene]

Hi there,

I hope someone can help me diagnose what is going on in my image of NGC6188. I took 16hrs of OSC images with my ASI294 and an IDAS D1 filter in suburban Sydney skies (Bortle 6). The images looked good as they came out of the camera but after stacking and stretching, I noticed a weird bloom in the middle of the image (see attached). No amount of processing can get rid of it.

I'm hoping it's not an issue with my camera as it's less than a year old.

Details:
SW Esprit 100
ASI294 MC Cool
IDAS D1 filter
485 x 120sec images
stacked in DSS with flats, darks, bias & dark flats
Processing in PixInsight

Cheers

Rene

[JA]

Hi Rene,

try stacking without the flats/darks etc... and see if there is any difference. Is the filter mounted OK- any issues? Are you using a genuine power supply or battery for the camera?

Best
JA

[Atmos]

It looks a bit like walking noise, have you been dithering?

[RugbyRene]

I have been dithering. But those streaks seem quite bad.

Rene

[Atmos]

From memory this camera doesn’t proceeds bias frames well, there is something that happens around the 4s mode where the camera changes so you’ll want your flats to be a minimum of 4s and not use bias.