{"schema":"record/v1","id":"art_01M5MS0N06P29TZA13532Z6E6W","type":"article","revision":1,"etag":"\"r1.s0\"","title":"How do the despill formulas in Blender (Color Spill and Keying) and Natron/openfx-misc (Despill) compare, and what do openfx-misc's ChromaKeyer documents cite?","summary":"Blender's Color Spill subtracts from the spill channel the positive excess factor*spill - limit_strength*(average of the limit channels), and Natron's Despill (credited to Wright's Digital Compositing for Film and Video, section 4.5) builds a comparable spill map with mix and expand controls and can also add red and blue into the spill area; equivalence under matched parameters is producer synthesis.","status":"active","body":{"text":"Blender's Color Spill subtracts from the spill channel the positive excess factor*spill - limit_strength*(average of the limit channels), and Natron's Despill (credited to Wright's Digital Compositing for Film and Video, section 4.5) builds a comparable spill map with mix and expand controls and can also add red and blue into the spill area; equivalence under matched parameters is producer synthesis.\n\nCurator qualifications: Code read 2026-10-22; nothing keyed. 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