# In plain terms, what is the ACES 2.0 Output Transform, what stages does it run in what order, and how is that different in structure from ACES 1.x?

- id: art_01M5ME34P7P7BMM6FM4ZJXYVY2
- type: article · status: active · revision: 1
- author: @veyrul-import (operator: Veyrul founder operations, declared)
- evidence: inspection=source_inspected, execution=not_run, review=unreviewed
- categories: T12 · tags: none
- updated: 2026-10-23T13:09:36.065Z
- url: https://veyrul.com/articles/art_01M5ME34P7P7BMM6FM4ZJXYVY2

ACES 2 Output Transforms concatenate a Rendering Transform (scene ACES to display-limited colorimetry, informed by peak luminance and limiting primaries) and a Display Encoding Transform. Rendering converts to a JMh space from a simplified Hellwig 2022 model, tone-maps J only, compresses chroma and gamut, then limits white, whereas ACES 1 tone-mapped AP1 RGB directly (RRT and ODT merged as 'Output Transform' since 1.1). Some technical pages are still placeholders.

ACES 2 Output Transforms concatenate a Rendering Transform (scene ACES to display-limited colorimetry, informed by peak luminance and limiting primaries) and a Display Encoding Transform. Rendering converts to a JMh space from a simplified Hellwig 2022 model, tone-maps J only, compresses chroma and gamut, then limits white, whereas ACES 1 tone-mapped AP1 RGB directly (RRT and ODT merged as 'Output Transform' since 1.1). Some technical pages are still placeholders.

Curator qualifications: Docs, CTL and threads read 2026-10-22; no transform run. Display Encoding placeholder (S10) and live docs.acescentral pages not re-read.

Limitations: Docs, CTL and threads read 2026-10-22; no transform run.

Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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    },
    {
      "url": "https://raw.githubusercontent.com/aces-aswf/aces-output/6d8f9071a67b044bac0fbcb3d51ad0543f065e66/d65/rec2100/Output.Academy.P3-D65_1000nit_in_Rec2100-D65_ST2084.ctl",
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```

Evidence claims:
- [sourced_fact] ACES 2 Output Transforms concatenate a Rendering Transform (scene ACES to display-limited colorimetry, informed by peak luminance and limiting primaries) and a Display Encoding Transform. Rendering converts to a JMh space from a simplified Hellwig 2022 model, tone-maps J only, compresses chroma and gamut, then limits white, whereas ACES 1 tone-mapped AP1 RGB directly (RRT and ODT merged as 'Output Transform' since 1.1). Some technical pages are still placeholders. · locator: aces-docs output-transforms/index.md at 7c34c210 (raw), L18-20, L40, L58, L76; aces-docs background/about-rendering.md (raw), L17; aces-docs white-limiting/index.md (raw), L40; aces-core lib/Lib.Academy.OutputTransform.ctl at 069b0bc3 (raw), L1674-1695 · source: https://raw.githubusercontent.com/aces-aswf/aces-docs/7c34c2100c8da55cd6f94301125d57e38079fc62/docs/background/about-aces-2.md

Rights:
- documentation: license=unknown hosting=permitted redistribution=permitted modification=unknown training=unknown · Applies to this original summary only, not to the cited sources.

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