ART and OpenColorIO

All this is very intersting! Thanks alberto.

Hi @agriggio
Thank you very much for this new feature!
I am very interested in luts in general as when they are well used, they are the easiest way for me to get a consistent look across a bunch of images.
I will take some time to experiment.

Hi @agriggio

I think if you add the function to manipulate ociomakeclf.exe from ART menu, it is useful for many users. Because I think it is difficult for non-developer users to install OCIO tools except on Mac OS, and without OCIO tools, especially ociomakeclf.exe, many users cannot enjoy this new feature of ART.
So, if you can distribute ART binary files including OCIO tools and add proposed function, it is helpful for ART users.
Thank you for your attention.

Hi,
And thanks for the comments!

I’ll see if I can include the needed OCIO tools in the binary distributions, or maybe if I can add the equivalent functionality to ART-cli. I have no plans to add a gui for this though, I think it’s difficult to come up with something reasonable and the benefit would be very limited.

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I’ve added links to pre-built binaries for ociomakeclf to the wiki page (scroll to the bottom): agriggio / ART / wiki / Luts — Bitbucket

Thank you for your quick response!

Resurrecting this fairly old thread, I could at last take a look at this new feature.
I read Alberto’s wiki page on the subject, and I converted ARRI and RED cube look LUTs to CLF LUTs.
Applying these LUTs form the Color/Tone correction and Film simulation modules works great, and I get pleasing looking images. So, thank you again @agriggio!

Now, I confess that I don’t understand a lot about the different transforms that are run under the hood. So here’s my question: is it correct to use the ARRI and RED CLF LUTs as they are, on a regular (SDR) monitor? I’m asking because I saw that the ACES LUT you provided above ( ACES ODT Candidate A - SDR.clf.gz) has SDR specified at the end of its name. If I’m not mistaken, the ARRI and RED cube LUTs are log-to-log, but I’m guessing that it is okay?

Hi,
If you followed the procedure in the wiki, the luts you get are meant to be used in scene linear space. So you can apply them in colour/tone correction, i.e. before the tone curve. If you use them in film simulation, you might still get a pleasing result, but such result could be different from the intended one. On the other hand, if you like it, who cares? :slight_smile:

That’s exactly the piece of information I needed. I don’t have the knowledge to really understand those spaces, even less so in relation with that ART processing pipe. So, thank you for this reminder.

Yes I followed the steps in your wiki page to produce the CLF LUTs. Most of them still look nice even in the Film Simulation module, but I’ll try and compare more between the two modules to see what differences it makes.

Hi,
There’s no need to understand the working spaces to use the luts. (You need to know something to create them, but that’s not the issue here). Whenever you use the lut, you will be in the correct space. The point I was trying to make (and I realise I did not do a good job at it) is that those luts are meant to be used in conjunction with an output device transform (ODT), which in art you would typically implement with the tone curve (plus log tone mapping if needed maybe) or with another lut applied towards the end of the pipeline. If you use them in film simulation, you are already towards the end of the pipeline, after the tone curve has already been applied. In that sense you are in the “wrong” place. But I write wrong in quotes for a reason, after all we are ARTists and so we are free to decide for ourselves what is right and what is wrong :wink: (yes this is supposed to be a joke)

Thanks Alberto, that’s clear now! Another advantage to have the LUTs loaded from the Color/Tone correction module, is that you can apply a mask to have the LUT applied to specific areas only. Very flexible!
A quick question regarding the camera input profile: what do you recommend for this, profile or no profile?

Profile, absolutely!

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… ARTful (or is that ARTfull?) ARTists! :laughing:
Not to compARTmentalize us, though.

Ok, I’ll stop now. :grin:

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I see a cartful of fans here. Maybe you should gather in a pub by the mart, and take part in social activities, like playing darts.

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smARTy-pants! :stuck_out_tongue_winking_eye:

(not my fault… @agriggio stARTed it!!)

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Not exactly a startling revelation. :smiley: I’ve heard that before.

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