This! I have wondered the same thing.

I wondered the same thing before I started researching. There are not that many ressources to learn stuff like that. I recommend scouring the internet for information and using paid websites or classes like mixing light and demystify colorgrading for example. I also recommend reading Steve Yedlin's paper: "on color science".Back to your question I would say commonly used software is: Lattice for exporting and editing LUTs, Fusion and even more prominently nuke, in nuke for example you can meassure pixel values for curves to create accurate FPEs. Some Color-Scientists use Matlab as far as I know. I'm by no means an expert, what I tell you here could also be wrong and there is a lot of stuff I dont know but as for grading practices most of this knowledge is not that important in my opinion because it takes a lot of knowledge and time to learn it and in the end creating a sophisticated FPE Lut using a chart, arri skypanel, densitometer, ... is just too much work for most people and most projects. Unless you work in the film industry. I started to try to code my own DCTLs but eventually returned to just being a user of, for example, the Tetrahedral interpolation dctl (Tetra) and Paul Dore's free DCTL library in combination with nuke's curves maybe. To code stuff like that you not only have to know how to code but also some color-science and some math. You might know all of this already but this is just something I wish someone told me before I invested so many hours a day looking into that topic ;). So maybe this helps!

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