In Rawtherapee, when using the film simulation LUTs, im wondering if its better to use a neutral RAW (without the Auto matched Tone Curve applied etc) or use the matched tone curve/auto levels and then apply the LUT, personally to me the LUT looks more realistic if its applied to the initial neutral profile RAW image, im just wondering if this is generally the correct way to go about it, and maybe add a little contrast, saturation etc to my liking after.
Or if anyone knows if within any of the LUTs, they have there own kind of tone curve built in?
As far as I understand, what LUTs do, at the very basic level, is replace colours in your image with the colours in the LUT that correspond to them. That being said, when the LUT is created, if contrast is changed as well, the resulting colours will also be brighter or darker as per the contrast change, so yes LUT files can tone curve changes built into them. As an example, for film emulation LUTs, when you load them, they produce a picture that looks the way it would look if it was shot with that camera, that lens, those internal settings, but with that particular film. So I guess when you have a film simulation LUT they apply the look and sometimes curve of the emulated film based on a flat response sample.
So short answer as far as Auto matched tone curve is concerned, try both, use the one that looks best.
You might find this little resource a good read…
Basically for the Lut to work as intended you do need to know its design/properties…what colorspaces does it work in etc etc…
Much of the technical nuance is covered in the article.
So if you meet the design conditions then it can work as intended otherwise nothing stops you from trying it and seeing if it gives you a look or feature that you find pleasing and or is useful…
I would likely try it without the automatch and just use exposure to guage what the lut would do to the image…in many cases just the changing of the model used by the tone curve can drastically change image saturation or end result of having added the curve to to confirm what the lut is doing it would likely be best to be more neutral…IMO but I am far far from being an expert…
You can play around on sites like this to try and create some of your own as well…