Picture Lock

Picture lock is the formal milestone in editorial where the director and editor agree that no further changes will be made to the cut. From that point forward, all downstream departments — sound design, music, VFX, color, mastering — work to a fixed timeline. Picture lock is signed off in writing or formally announced because every minute of subsequent change cascades through enormous downstream costs: sound effects need to be re-synced or re-created, music cues lose timing, VFX shots may need re-rendering, color grading on the affected segments has to be redone. In a structured production, picture lock happens after a series of editorial milestones: rough cut, director's cut, producer's cut, fine cut, locked picture. The lock is sometimes preceded by 'picture lock for sound' and 'picture lock for VFX' if certain departments need to start earlier. Practically, picture lock means the conform reference (the EDL/XML/AAF) becomes authoritative and any further change requires re-conform and partial redo of downstream work. Streaming releases sometimes break this discipline with last-minute editorial tweaks for ratings or compliance, which post houses internally call 'picture lock with carve-outs' — costly and risky. The discipline of true picture lock is one of the strongest predictors of an on-budget, on-schedule post-production. Reference: editorial workflow standards from PGA (Producers Guild of America) and various studio post-production handbooks.