I work for/with/teach pro colorists. I create & test LUTs both in Pr and in Resolve.
LUTs are called by colorists "the dumbest math out there" ... because they really aren't math. They're simply a look-up table set of data applied to a clip, nowhere as near sophisticated as say a tonemapping algorthm. The most complex can do wondrous things ... but only if they are the correct LUT for the media, and if the media is exposed as the LUT was built to handle.
If you apply a LUT that has any expectation your clip doesn't have, it will clip highlights or crush blacks, and you cannot retrieve that data after the LUT.
And just because it visually "looks ok" ... that LUT may be damaging pixels, or causing artifacts that you might not have noticed. So you add a bit more correction touch to the image, and ... what the Hades? Where did that come from? Right.
That said, colorists do tend to use them heavily because they can be an effective tool. BUT ... they test the Hades out of a LUT before they use it on client material. Find under what circumstances it breaks their clip, because guaranteed ... under the right circumstances, any LUT will break the media.
Many of the colorists I work with do download say all the Red, Arri, Sony, Canon, and Panny "factory" LUT conversions options. Test them. But quite often, after seeing what they do, they 'roll their own' which they use instead. Or perhaps, make several variants for different scene types/cameras/camera exposure/whatever.
But the LUTs they use do not replace complex grades on any clips. They are only a part of the process, used to solve a specific problem. Their grades still use typically 'fixed node structures' from 12 to 40 nodes in Resolve, with a LUT in one or two of them. With qualifiers typically involved pre/post that LUT.
That's why Ann is not a huge fan of LUTs ... most users simply do not have the technical knowledge to really use them safely and correctly. They don't understand why & when a LUT is used, why & when other things are used. And they often expect a LUT to simply fix the entire grade.
They are sold on many sites as simple "we fix all your image ills and make it BEAUTIFUL in one click!" solutions.
And ... some of them actually can work nicely ... but only if ... your media has very close to the same exposure and scene contrast/camera settings as used for the media the LUT was built from.
If your clip is a bit under-exposed, over-exposed, the scene has higher or lower contrast, you saturation settings are different ... it probably will not match the look you expect. Do you know how to work around that? If so, feel free. If not, well ... you have some study ahead of you.
If someone offered you a magic elixir that fixed your aches, pains, prevented arthritis and aging, would you buy it?
Neil
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