Which Dolby Vision trim passes must a colourist actually do for HDR-to-SDR delivery, in what order, and how many targets?

Dolby's guide requires the colourist to review the Rec.709 100-nit mapping across the whole timeline, and to make the 100-nit trim first if any shot is trimmed; extra targets (600/1000 nit) are optional, up to four trims per deliverable, and should be real passes rather than pasted values. Netflix (2022 and 2026-07 snapshots) says HDR is graded first, followed by analysis and a shot-by-shot trim pass, but lists the 100-nit L2/L8 trim values themselves as not required unless creatives want scene-level adjustments. The two statements are compatible if 'review the default mapping' (Dolby, required) is separated from 'deliver authored trim values' (Netflix, optional); the sources do not say so explicitly. Curator qualifications: 9 of 9 excerpts present (E5 phrase occurs twice on the Netflix page). Dolby: check the 100-nit mapping for all shots; the SDR 100-nit Rec.709 trim is required as the foundation for interpolation; up to 4 target trims per deliverable; pasting the same L1 across a reel is not acceptable; CMv4 secondary trims are ignored in the 2.9 backwards-compatible block. Netflix: HDR graded first, then analysis and a shot-by-shot trim pass; 100-nit L2/L8 values included only if creatives make scene-level adjustments. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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  "citations": [
    {
      "url": "https://professional.dolby.com/siteassets/pdfs/dolby_vision_best-practices_colorgrading_v4.pdf",
      "note": "Dolby Vision best practices colour grading v4 PDF (equals pin), sections 2, 4.1, 4.3; Wayback 20260726130744 Netflix 'Dolby Vision Metadata Overview' (equals pin); Wayback 2022-06-08 Netflix 'Dolby Vision HDR Mastering' (equals pin)"
    },
    {
      "url": "https://partnerhelp.netflixstudios.com/hc/en-us/articles/360058735254-Dolby-Vision-Metadata-Overview",
      "note": "Dolby Vision best practices colour grading v4 PDF (equals pin), sections 2, 4.1, 4.3; Wayback 20260726130744 Netflix 'Dolby Vision Metadata Overview' (equals pin); Wayback 2022-06-08 Netflix 'Dolby Vision HDR Mastering' (equals pin)"
    },
    {
      "url": "https://partnerhelp.netflixstudios.com/hc/en-us/articles/360000599948-Dolby-Vision-HDR",
      "note": "Dolby Vision best practices colour grading v4 PDF (equals pin), sections 2, 4.1, 4.3; Wayback 20260726130744 Netflix 'Dolby Vision Metadata Overview' (equals pin); Wayback 2022-06-08 Netflix 'Dolby Vision HDR Mastering' (equals pin)"
    }
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