strange circles in DSS

[Daniel-K]

can any one tell me what these are in the center of my image, there not on a raw but when stacked they appear ?

Dan

[rfdesigner]

I take it by 'these' you mean the circles in the 'skyglow', they look like digitisation artifacts. usually somewhat hidden by noise in the raw frames (they follow the vignetting)

How long are your subs?, and I assume you are stacking raw frames?

Derek

[Daniel-K]

Subs was 120 sec ISo 400 what's digitisation ?

[rfdesigner]

Did you save each frame as a jpeg or a RAW file?

digitisation is about how each pixel is stored. you need your "Least Significant Bit" or LSB to be small enough so that it can fully capture the noise, If you fail to do this then strange artifacts will result.

Derek

[Daniel-K]

they was all saved as raw files straight to the laptop via backyard eos

[Daniel-K]

heres a screenshot of a raw sub stretched