Digital intermediate (DI)

The DI refers to the process that accepts exposed film or digital footage and eventually delivers edited and graded masters, which can either be film internegatives for production labs to generate large numbers of release prints, but today usually the Digital Source Master (DSM). Initially the term arose to describe a digital version of the traditional chemical intermediate lab where film is graded, cut and copied from camera negative to several interpositives, then to many internegatives, which are distributed to the production labs to make the release prints for cinemas. These processes include creating possibly thousands of release prints from a single set of camera negatives.

Although the boundaries may vary, generally the DI ‘lab’ accepts data from digital movie cameras, and outputs an edited and graded DSM or, possibly, an internegative master for a whole or part of a feature. However, the operation and decision-making processes of the digital workflow greatly differ from the traditional film lab, not least because of the interactive nature of the digital operation.

In the DI lab, decisions become on-screen reality and are seen in full context as they are prepared – no waiting for the ‘chemical’ lab. Grading, dissolves, cuts and effects can be seen immediately – on a big screen if needed. The interactive process allows more creativity and gives complete confidence that the decisions work well. Also grading can take place after the footage is cut together, so the shots are seen, as graded, in context.

For those still using film, whole movies can be sent for output to the digital lab’s film recorder, exposing 1000ft reels at a time and no final grading required. For digital cinemas, the DSM – digital cinema’s equivalent of internegatives – enters a short process to create the Digital Cinema Package (DCP) for distribution.

See also DCI