Error: "the image contains many negative pixels (99%), calibration frames are probably incorrect"

Software Siril
1

Hello,

I love using Siril, its my favourite processing software.

I am using Siril 1.2.0-beta2 on Windows that I downloaded from the website.

After running calibration I get the error “After dark subtraction, the image contains many negative pixels (99%), calibration frames are probably incorrect.”

My darks are 60s of exposure, same as my lights 60s. The issue only occurs when I try to use a master bias then my master dark or the reverse order, but if I use either of them individually I have no issues. The bias frames are 1/4000 s.

image

The error frame produced is called pp_V10blue.

I’ve been running into the same error a few times and I’m only bringing it up now. My solution in the past has been to use dark frames in my calibration but not bias. I’m hoping someone could explain to me either a solution I could apply in Siril or inform me as to whether I have a misunderstanding of how calibration works.

Thanks for taking the time to read.

2

Hello, a dark frame already contains the bias data, removing twice the bias data will result in mostly negative pixels with modern sensors. Please take a look at the tutorials: Siril - Tutorials

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3

Thank you very much for enlightening me. My understanding, after reviewing the tutorial on manual processing you linked me to, that the master-bias frame is stacked and is then applied when calibrating the individual flat frames before stacking them to make a master-flat?

4

that’s correct

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