Pulldown

Confused by the term Pulldown, or Telecine?

Here are the facts:

24p = 23.98 fps (Progressive)

29.97 fps = 59.94 interlaced fields per second, aka 60i

• Interlaced video displays 60 half frames per second

• Progressive video takes entire video frames on the go

• Progressive video requires 2x the bandwidth of interlaced video

Pulldown (Telecine)

This is the conversion process: 24p (film or video) — 29.97 (video).

• 2:3, or 3:2 (aka 2:3:2:3): 60 fields / 24 = 2.5. So each frame of 24p material needs to last for 2.5 frames of video

• 2:3:3:2 is referred to as Advanced Pulldown

Excerpt form Videomaker Magazine:

Here’s how it works: we are transferring 24p to 60i, which means we are converting 24 frames per second into 60 fields per second. The first frame of film is transferred to the first two fields of video and the next frame of film is transferred to the next three fields – 2:3. This results in some frames of film spanning two different frames of video or, to put it another way, some frames of video that are composed of fields from two different frames of film.

-paul.

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