of course… the point is that for DSLR images, a good raw converter like Raw Therapee is an alternative to conventional astro processing.
Some people would say it is not quite as good, but is more convenient. However, with the inclusion of lens profiles it is arguably much more capable than conventional processing.
I don’t know where in the processing the lens profile is applied, but I don’t see how that matters to astrophotography.
It is possible that it is done before debayering the CFA. It is possible it is done after. The Raw Therapee people would know.
Vignetting correction could happen either time. So could distortion correction.
In general one wants pixel operations to occur on linear data. Lens profile corrections ARE done to linear data - so I don’t see why this would be problematic.
In RT you can correct CA before demosaic for bayer CFA. Other correcctions (vignetting, distortion) are applied later in the pipeline (in RGB ar Lab space)
Edit: Flat field vignetting correction in RT is also applied before demosaic.
In the workflow described one NEVER needs to subtact biases and darks.
You just raw convert with Raw Therapee.
Commercial camera sensors and their firmware typically do a lot of these processes automatically. The empirical fact is that you often don’t need to do this in order to get results comparable to conventional astro processing.
Now it so happens that Raw Thearapee also allows you to give it dark frames and (I think) bias frames. So it could do that, but I don’t use it that way.