OpenColorIO 2 Configs for ACES

Discussions - Using ACES
21

@TooDee Golly that does look quite skewed in that video!

The difference between the two configs I believe is that the ACES-CG config is using a built-in transform for the sRGB display:


  - !<ColorSpace>
    name: Display - sRGB
    family: Display
    equalitygroup: ""
    bitdepth: 32f
    description: Convert CIE XYZ (D65 white) to sRGB (piecewise EOTF)
    isdata: false
    categories: [file-io]
    encoding: sdr-video
    allocation: uniform
    from_display_reference: !<BuiltinTransform> {style: DISPLAY - CIE-XYZ-D65_to_sRGB}

while the Maya one is not:


  - !<ColorSpace>
    name: sRGB
    family: Display
    description: |
      sRGB monitor (piecewise EOTF)
    isdata: false
    categories: [ file-io ]
    encoding: sdr-video
    from_display_reference: !<GroupTransform>
      children:
        - !<MatrixTransform> {matrix: [ 3.240969941905, -1.537383177570, -0.498610760293, 0, -0.969243636281, 1.875967501508, 0.041555057407, 0, 0.055630079697, -0.203976958889, 1.056971514243, 0, 0, 0, 0, 1 ]}
        - !<ExponentWithLinearTransform> {gamma: 2.4, offset: 0.055, direction: inverse}
        - !<RangeTransform> {min_in_value: 0., min_out_value: 0., max_in_value: 1., max_out_value: 1.}

You could confirm that by swaping in that groupTransform in place of the BuiltinTransform in the ACES-CG config.

While you’re at it, you may want to consider using the pure 2.2 display instead

 - !<ColorSpace>
    name: Gamma 2.2 / Rec.709
    family: Display
    description: |
      Gamma 2.2 monitor with Rec.709 or sRGB primaries
    isdata: false
    categories: [ file-io ]
    encoding: sdr-video
    from_display_reference: !<GroupTransform>
      children:
        - !<MatrixTransform> {matrix: [ 3.240969941905, -1.537383177570, -0.498610760293, 0, -0.969243636281, 1.875967501508, 0.041555057407, 0, 0.055630079697, -0.203976958889, 1.056971514243, 0, 0, 0, 0, 1 ]}
        - !<ExponentTransform> {value: 2.2, direction: inverse}
        - !<RangeTransform> {min_in_value: 0., min_out_value: 0., max_in_value: 1., max_out_value: 1.}
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