Need help configuring ACES pipeline for CG and Nuke.


(Luka Jgharkava) #1

Hi

We are about to implement the ACES pipeline in our studio projects and I want everything to be correct. I’ve read lot about the ACES pipeline, I think I’m on the right path but please correct me if I’m wrong.

So, the project that we are starting is shot on ARRI RAW. There are lots of shots that need VFX. We are doing CG in Maya and Houdini for this project.

Here is what I’m planning to do:

  1. Convert every ARRI RAW shot to ACES2065-1 EXRs using NUKE
  2. We work on CG using Maya and render it with ACES-CG
  3. Open blank NukeX, import previously converted ACES2065-1 EXR. Using OCIOColorSpace node, change in to ACES - ACES2065-1 and change out to ACES - ACESCG.
  4. Import Maya renders which are rendered in ACES-CG.
    5, Composite everything.
  5. When compositing is done, change in to ACES - ACESCG and change out to ACES - ACES2065-1.
  6. Add write node, put ACES - ACES2065-1 in colorspace and export for color grading.

Is this workflow correct? Am I missing something or will this kind of workflow work perfectly with every step of the project including color grading.

Thanks in advance.


(Kristian Krebs) #2

Hi Luka!

I would like to post in this thread because I´m also working on how to implement ACES into our pipeline at a studio, producing mostly still photography but also more and more films or spots. Our film pipeline is completely based on ACES color management and is very new. Currently we are educating people at our facility in order to get it running.

We use NUKE for scripting purposes, to help our 3d artists, working in 3d Studio Max. We will use NUKE for compositing in the future if everything goes well and I´m studying hard to try to understand how to make this work.

I´m not an expert and I´m not working with VFX, I´m a photographer, but I want to try my theory here. So…

We are converting our footage from RAW to online media in DaVinci Resolve. To our knowledge Resolve is the only affordable software able to convert our media into ACES2065-1 or AP0 EXR:s. For ARRIRAW it could also be done in ARRIRAW Converter but maybe not as smoothly. For VFX this should be pretty much it, as the camera media is now linear.

I don´t know Maya but from 3d Studio Max I think the artist can render linear media, or I really hope so:-)

These linear files from the camera and 3d should be the simplest working solution for NUKE. Therefore I think you can skip the rendering of ACEScg and just go for the linear media straight away. To my knowledge the ACEScg is linear but not AP0, it´s AP1 which is a smaller color space, rec2020.

The composition made in NUKE should be rendered out as linear media for use with the other linear AP0 onlines in the color grading software, and they should hopefully match.

To be able to do the matching in NUKE according to the color grade I think you would have to use a LUT or CDL sent to you from the grading people, but this I haven´t tried yet as my knowledge in NUKE is to limited.

I would not say that this is the correct solution but this is our thoughts so far, to keep everything simple and linear :slight_smile:

All the best!
Kristian Krebs