ACES Output Transform Evaluation and Feedback - 3 Candidates

Participants in this working group have been collaborating for the past year to develop updated ACES Output Transforms (“RRT+ODTs”) for consideration for ACES 2.0.

The group has reached a milestone by developing three potential display transforms that are each based on fundamentally different principles. At this point, feedback from potential end-users is critical in helping the group move forward with development.

This test presents a major fork in the road and we need the larger community’s input to steer the group. We have reached out to a long list of colorists individually since their feedback is critical, but this testing can also be done by anyone involved in image-making. Please also share with your colleagues who might not be following along closely with ACES development.

To that end, below are a few links to different resources that are associated with the test we are asking all to participate in:

The Candidates

The three candidates (labeled A, B, & C) are implemented for Resolve, Baselight, and Nuke (via OCIO).
There is an SDR and HDR version of each candidate.
The SDR transforms are intended for Rec. 709 (i.e. 100-nit, Rec.709 primaries, BT. 1886).
The HDR transforms are intended for Rec. 2100 (i.e. 1000-nit, Rec.2020 primaries, ST-2084 [PQ] ).

It is important to note that none of the three candidates should be considered “final”. However, the group is hopeful that feedback received from this testing phase and associated survey will help identify the most-favored behaviors that should be polished (and which behaviors are showstoppers that should be abandoned) so that the group can better focus its development efforts during the next phase of transform development.

The entire package is downloadable as a ZIP file from Github containing everything you’ll need to install on any of the three systems listed above.

Download package from Github (.zip)

Selected Sample Image Set

The group has curated a small image set of still frame ACES OpenEXRs from various sources. These can be used along with any of your own test material when evaluating the transforms.

Download image set from Github (.zip)

The same frames above can also be viewed as pre-rendered comparisons embedded in a webpage - "ACES OT Candidate testing examples"

(Note: At the moment, proper HDR viewing of this page is only known to work correctly under certain versions of Google Chrome)

The Survey

Once you’ve made yourself familiar with the look and behavior of the transforms, the group asks that you capture your thoughts and feelings in one of two survey forms, depending on if you worked in SDR only or were able to compare SDR and HDR. This feedback is the most important part of this test.

We know that your time is valuable and limited, but if you take time to install the transforms and compare their behaviors, we ask that you please, please, please take a few minutes to funnel your reactions back to the group.

While we surely hope you are able to take adequate time with the process, cursory or partial feedback is better than no feedback at all.

For those viewing the SDR versions only:

For those viewing SDR & HDR:

Please let us know if you have any questions or feedback about the process itself and we thank you in advance for your contributions.


If working with Resolve, please pay special attention to the README file regarding the installation path. The install path for custom ODTs such as those provided here is different than the normal LUT directory where DCTL files traditionally go.


1. Adding a Custom ACES IDT or ODT File:

  • Navigate to the ACES Transforms folder in Resolve’s application support folder.
    • MacOS: ~/Library/Application Support/Blackmagic Design/DaVinci Resolve/ACES Transforms/ODT
    • Windows: C:\Users\<User>\AppData\Roaming\Blackmagic Design\DaVinci Resolve\Support\ACES Transforms\ODT
    • Linux: ~/.local/share/DaVinciResolve/ACES Transforms/ODT
1 Like