Deep sky stacker - Calibration

[Guest]

I use deep sky stacker for calibration and registration of images but I wanted to clarify one aspect.

I start with cr2 files directly from my canon camera. DSS builds the master darks, flats, bias and so on and then calibrates the lights. I get DSS to save the intermediate files as FITS files which at that stage have three colour layers - RGB. So my question is - does DSS treat all these three colour slices as separate images all the way through the process?. So when it builds the master dark for example it combines all the red slices, then all the green slices and then all the blue slices. And does it do that all the way through? So when it combines the master dark with the lights it does each colour slice separately resulting in a file which still has three separate colour layers? I know that the intermediate FITS files do have three separate colour layers.

 

[nephilim]

On 17/12/2020 at 07:03, woodblock said:

I use deep sky stacker for calibration and registration of images but I wanted to clarify one aspect.

I start with cr2 files directly from my canon camera. DSS builds the master darks, flats, bias and so on and then calibrates the lights. I get DSS to save the intermediate files as FITS files which at that stage have three colour layers - RGB. So my question is - does DSS treat all these three colour slices as separate images all the way through the process?. So when it builds the master dark for example it combines all the red slices, then all the green slices and then all the blue slices. And does it do that all the way through? So when it combines the master dark with the lights it does each colour slice separately resulting in a file which still has three separate colour layers? I know that the intermediate FITS files do have three separate colour layers.

 

This has me curious now. I'd have thought that it wouldn't though as when imaging RGB with a mono camera I'm sure you have to also take seprate  calibration frames in each colour channel.

[vlaiv]

I don't know how DSS works - but for calibration you don't need to do color separation yet, and indeed it is better not to do it until you finish calibration.

[Guest]

I've raised this topic on the DSS forum and there is some discussion and disagreement between the experts and I'm keen to hear what they decide. I'll post back on here when I know.