PreProcessing of images with multiple ISO and exposure values

[John_Gill]

Hi,

When doing BatchPreProcessing of images with multiple ISO and/or exposure values should you process each "group" of images separately and then integrate or can you load everything at once and let PIxInsight handle the differences.

Regards
John

[Juan Conejero]

To maximize SNR and achieve the best possible outlier rejection, you should always integrate everything in a single operation. You should also register all frames in a single operation, against the same reference image, to minimize interpolations.

[John_Gill]

Hi Juan,

Thanks for your answer, it is a great help.

Regards
John

[pfile]

to add to this though, calibration should be done separately for each ISO. the flat calibration will definitely be wrong if the flat ISO differs from the bias/dark ISO when BPP is calibrating the flats, and this will lead to overcorrection of the lights when they are calibrated with the miscalibrated master flat. same goes for the lights - need matching ISO darks and bias while calibrating the lights.

rob

[gerlos]

So, if I've sets of shots taken with different ISO, it should be safer to calibrate flats and apply them in a different step, is it right?