24P

Refers to 24 frames-per-second, progressive scan. 24 f/s has been the frame rate of motion-picture film since the ‘talkies’ arrived. It is also one of the frame rates allowed for transmission in the DVB and ATSC digital television standards, so they can handle film without needing any frame-rate change (3:2 pull-down for 60 f/s ‘NTSC’ systems or running film fast, at 25f/s, for 50 Hz ‘PAL’ systems). 24P is now accepted as a television production format – usually associated with high definition 1080 lines to give a ‘filmic’ look on 60 Hz TV systems. Drop-frame frequencies (e.g. 23.976Hz frame rate) may be used in in North America and other previously ‘NTSC’ countries).

A major attraction of 24P is its relatively easy path from this to all major television formats as well as offering direct electronic support for motion picture film and D-cinema. However, the relatively slow frame-refresh rate has drawbacks. For display it needs to be double shuttered – showing each frame twice to avoid excessive flicker, as in cinema projection, and fast pans and movements are not well portrayed. Faster vertical refresh rates are generally preferred for sports and live action.

See also: 24PsF, 25P, 3:2 Pull-down, ATSC, Common Image Format, Digital Cinema, DVB, Versioning