New to Siril here, many doubts… This is probably a FAQ, but I was unable to find it. Sorry if it is somewhere.
It is regarding the sentence in the Siril’s manual that states:
“Note that BIAS frames MUST be taken at the same ISO than light frames.”
I do not understand why this is. Please allow me to explain myself:
If I take only lights and darks (taken at the same ISO as lights of course), I do not need bias since it is already implicitly included in the darks. So, bias are used to calibrate the flats (this is pretty clear in Siril scripts!). Hence, bias should be taken at the same ISO as the flats, not the lights. And the flats should be taken at lowest ISOs because the nature of its correction (vignetting, sensor and lens dirt, etc).
Hence, in general I would take, say, ISO5000 lights and darks, and ISO100 flat and bias.
What am I missing?