Just gunzip it, it’s xml. I manually translated the various steps you outlined above (as seen in the OCIO config file) to the equivalent CLF nodes. Specifically, the CLF file contains 9 process nodes, which do the following:
Matrix node from ACES 2065-1 to XYZ
Matrix node from XYZ to linear Rec.709
Range node to clamp negatives
Matrix node doing the “inset” transformation above
Log node to convert from linear to log2
Range node to remap the log range [-12.47393, 4.026060] to [0,1]
the per-channel curve as a LUT1D node, obtained with ociomakeclf from the original in the github repo
Is the ability to use this now baked in to ART or does it need to be compiled to access it. I noted somewhere something about a flag to set for compilation. I have been lazy for some time now as a while back I couldn’t get ART to build on Windows… Would it be in the latest windows nightly binaries??
I don’t know about the nightly binaries, but it’s definitely in the latest “official” version. (And yes, it needs to be enabled at compile time).
Based on this description, looking at the CLF file and a brief test, it seems to work. I haven’t yet setup the original config in Blender so didn’t do an exact conversion yet but qualitatively it matches what I’ve seen in my own experiments and some done by others.
Neutral profile as a starting point (so that no tone-mapping was applied). Just loaded the LUT and this was the result. It is as expected. Well done Should be something quite interesting to experiment with for the folks here.
Thanks for checking!
Fwiw, qualitatively the output is a bit too flat and desaturated for my taste, but you can probably fix that with a bit of “look” tweaks.
I prefer the current ACESnext candidate A out of the box, or even better the RED “medium contrast, medium rolloff” one, as it is closer to a finished image. But these are just personal preferences…
There are several creative looks but also the ”AgX Chroma Laden” look which adds a saturation increase on top of the AgX Base look. That should be more like a ”finished image” type of starting point. But yes, personal preferences indeed.
Great, thanks! I’ll see if I can convert those to clf as well. I skimmed through the thread linked above but I didn’t have the energy to read all the 900+ posts in it…
Yeah, no need. Eary’s most recent config contains also a spherical compression (done before the image formation) but that is still the topic of ongoing experimentation and it’s not yet settled on.
Here’s the “chroma laden” version of AgX as a CLF. This time I used a different approach to create the LUT, leveraging ociobakelut plus some log shaper at the beginning to ensure that it is applicable to a suitably large dynamic range. It looks ok to me (in the sense that the contrast is similar to AgX but it’s more colourful), but independent checking would be good.
You can use it in ART either by uncompressing it, or by changing the extension to .clfz.
Hi, I revisited the blenderartists thread and saw a lot of activity there. So, here’s an updated AgX for ART based on the latest version by Eary_Chow. (To use it, either uncompress it or change the extension to .clfz) AgX - EaryChow.clf.gz (1.4 MB)
For those interested, there’s now an open pull request to replace Filmic (as in Blender’s current picture formation method, not to be confused with darktable’s filmic) with AgX in Blender.
@flannelhead do you know where I can find more info about how the guard rail works? I only see a LUT in the repository, but I’d be interested in the details of the algorithm. Thanks in advance!
As I have followed the thread quite closely and took part in the guard rail experimentation, I can probably answer at least some questions if such arise from reading the links @agriggio
Awesome, thanks to both! I will read the material and get back with questions. Basically I’m trying to understand whether the guard rail can support HDR screens (say 1000 nits). I quite like how it handles the “path to white”, but the AgX config seems to be limited to SDR as far as I understood, which is a pity. (If I’m wrong, even better