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Alex ChambersandClaude Opus 5.5
5a61fc5f67
Sony's Dynamic Range Optimizer (factory default Auto) brightens the darker regions of the camera JPEG, not the raw. The tone curve fitted to that JPEG carried the brightening into the raw's starting look: on 8 ILCE-7CR photos with DRO on, LightCraft rendered +6.4 L* from Lightroom's default (median dE76 7.5), against -0.2 L* (3.6) for the 16 with DRO off. - lightcraft_raw::embedded_preview_dynamic_range_optimized reads Sony maker-note tag 0xb025 (every documented value: 0 off; 1-3, 8-12 and 16-23, i.e. up to Lv8, on). It was present on all 264 Sony raws checked (98 bodies); 0xb04f only says on/off and is missing on older bodies. - With DRO on, the look keeps the colour fitted to the JPEG and its tone curve is lowered, knot by knot, to Sony's curve without DRO wherever that is darker (assets/camera-tone/sony-dro-off.json, pooled from 12 CC0 raw.pixls.us ARWs of 10 interchangeable-lens bodies; sources and derivation in the file and assets/ATTRIBUTION.md). The second-last knot is lowered only as far as keeps the shoulder past the last knot at or below the fitted curve, so the result is never brighter anywhere. Compacts that map raw values darker keep their own curve. - DRO off, unknown and other makers: unchanged (byte-identical renders on 71 + 35 photos). Render cache version 23. DRO-on photos now land at +0.8 L* from Lightroom (median dE76 3.3), band by band like the DRO-off ones. Docs: camera-preview-colour.md, parity row. Co-Authored-By: Claude Opus 5.5 <[email protected]>