XML color correction format storing ASC parameters, portable between systems — transfer grades from set to final DI without recalculation. Industry standard.
On set or immediately after shooting, the colorist packs the initial grades into a format that every system understands: CDL — an XML file that stores the ASC parameters (Slope, Offset, Power) for each clip. The key advantage: You can transfer this list from the DIT cart to the editing system, then to the final color suite, without the grades needing to be re-rendered or recalculated. The values remain identical because the format is standardized.
In practice, this means the following: The DIT works on set with the camera system (RED, Alexa, whatever), performs quick preliminary color checks, and exports the CDL. The editor in the edit suite can already integrate this into their timeline, thus having a consistent image instead of raw footage immediately. Later, in the finishing suite, the final colorist loads the same CDL, sees exactly what was decided on set, and builds upon it or discards it — but the workflow is continuous. No loss of information, no 1:1 re-imports necessary.
CDL is proven on large productions where multiple systems work in parallel. You might have a complex timeline in DaVinci Resolve, an editing station in Premiere or Avid — both understand CDL. An important point: CDL only stores the color values, not the effects or the look itself. This means complex curves, vignettes, or sepia effects don't disappear, but they are not included in the CDL dataset. This is intentional — CDL is the foundation, the technical handshake.
Practice also shows its limitations: for highly individual looks (e.g., LUTs you've designed yourself), CDL alone is not sufficient. You will also need the original document (the DaVinci project itself) or a separate look description. CDL is therefore the first safety net, not the entire security system. However, it is indispensable for standard corrections and the rapid flow of information between departments.