One way to process a DSLR astro image is to go through a calibration process to produce a linear image. This involves collecting flats and darks and making master images. Software advances have made it easier to create the necessary files, but it is still a length and tedious process.
For a unique astro camera attached to a (potentially) unique optical train in a telescope that's what has to be done.
But for a DSLR that is to a large extent and standard product, using lenses that are also standard products, there is an alternative - shoot in RAW format and then use a high quality RAW converter which includes lens and sensor specific corrections for vignetting and distortion . Although raw conversion software typically applies a nonlinear tone curve, one can get most software to not do that step. This generally involves having the software output use a profile that specifies a linear tone curve.
What you are left with is a calibrated linear file that is much like the output of the astro-style full processing.
A raw converter like Raw Therapee (RT) can do all that, as well as apply darks and flats (although it does not help you make the masters).
Has anybody tested the two approaches head to head recently?
I was using RT to make linear files for a terrestrial photo project when I came across a discussion of using Raw Therapee by Roger Clark https://clarkvision....th-rawtherapee/ and https://clarkvision....age.processing/ written in 2016- 2018.
He is correct in general that RT is an excellent raw converter, with tons of options you don't get in Adobe Camera Raw or other converters. That said, I am not sure that Clark's workflow as discussed in those web pages produced fully linear output files because he does not mention using an output profile with RT which is necessary to get fully linear output.
But regardless of whether his workflow was full linear, he has a point that it is a lot more convenient to use RT. Have others tried this comparison since then?