A method used to map the 24 or 23.98 f/s of motion picture film onto 30 or 29.97 f/s (60 or 59/94 fields) television, so that one film frame occupies three TV fields, the next two, etc. It means the two fields of every other TV frame come from different film frames making operations such as rotoscoping, standards conversion and editing difficult. Equipment is available to unravel the 3:2 sequence to allow clean frame-by-frame treatment and subsequently re-compose 3:2.
The 3:2 sequence repeats every 1/6th of a second, i.e. every five TV frames or four film frames, the latter identified as A-D. Only film frame A is fully on a TV frame and so exists at one timecode only, making it the only editable point of the video sequence.
3:2 pull-down creates a field-based result in that every other frame contains frames comprising two different fields. This makes subsequent compression, which then has to be based on 60 fields/s, less efficient than working with 30 frames/s. This may affect delivery platforms from TV broadcast to DVDs.