Mastering

Once the grading is approved, the film is artistically complete—but far from ready for delivery. Mastering is the step in between: from the final picture and sound conform, the master is created, the technically defined source from which all delivery formats are derived. Cinemas require a DCP, streamers usually demand IMF packages according to their own specifications, broadcasters and archives require other formats. Each deliverable has a specification sheet: codec, color space, resolution, audio track assignment, subtitles, metadata.

Versioning: One Film, Many Versions

Hardly any film leaves post-production as a single file. There are language versions with their own audio and title cards, subtitle versions, cut versions for specific markets or age ratings, airline versions, trailer masters. The IMF format is built precisely for this: it stores the common material once and describes each version as a composition list that only references the differences—instead of rendering a completely new file for each version. Those who plan versioning only at the end will pay double for it.

QC as Gatekeeper

Quality Control stands between mastering and delivery. It checks technically—dropouts, artifacts, audio sync issues, loudness, color space violations—and content-wise: are the title cards correct, are the subtitles in place, is the correct cut version in the package? Streamers and distributors conduct their own incoming QCs and completely reject packages with errors. A rejection costs time and often money; therefore, in-house QC is considered the last instance that no master can bypass.

• Obtain delivery specifications from the recipients before grading, not after—the master's color space and resolution depend on them.
• Determine versioning logic early: which versions exist will decide how title cards and VFX shots need to be set up.