Adobe Premiere Pro CS6 User Manual
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About 3:2 and 24pA pulldown
When you transfer 24-fps film to 29.97-fps video, you use a process called 3:2 pulldown, in which the film frames are distributed across video
fields in a repeating 3:2 pattern. The first frame of film is copied to fields 1 and 2 of the first frame of video, and also to field 1 of the second video
frame. The second frame of film is then spread across the next two fields of video—field 2 of the second video frame and field 1 of the third frame
of video. This 3:2 pattern is repeated until four frames of film are spread over five frames of video, and then the pattern is repeated.
The 3:2 pulldown process results in whole frames (represented by a W) and split-field frames (represented by an S). The three whole video frames
contain two fields from the same film frame. The remaining two split-field frames contain a video frame from two different film frames. The two split-
field frames are always adjacent to each other.
The phase of 3:2 pulldown refers to the point at which the two split-field frames fall within the first five frames of the footage. Phase occurs as a
result of two conversions that happen during 3:2 pulldown: 24-fps film is redistributed through 30-fps video, so each of four frames of 24-fps film is
spread out over five frames of 30 (29.97)-fps video. First, the film is slowed down 0.1% to match the speed difference between 29.97 fps and 30
fps. Next, each film frame is repeated in a special pattern and mated to fields of video.
When you apply 3:2 pulldown to footage, one frame of the film (A) is separated into two or three interlaced video fields (B) which are grouped into
video frames containing two fields each.
It’s important to remove 3:2 pulldown from video footage that was originally film, so that effects you add synchronize perfectly with the original
frame rate of film. Removing 3:2 pulldown reduces the frame rate by 1/5: from 30 to 24 fps or from 29.97 to 23.976 fps. Reducing the frame rate
also reduces the number of frames you have to change.
Premiere Pro also supports Panasonic DVX100 24p DV camera pulldown, called 24p Advance (24pA). This format is used by some cameras to
capture 23.976 progressive-scan imagery using standard DV tapes.
Chris Meyer provides links to resources about pulldown
on the ProVideo Coalition web site.
Create a 24p sequence
1. Select File > New > Sequence.
2. From the Available Presets list on the Sequence Presets tab, choose the 24p preset that matches the frame aspect ratio and audio sampling
rate of most of your footage. 24p presets are located in the DV-24p, DVCPRO50 > 480i, DVCPROHD > 1080i, and DVCPROHD > 720p
folders.
3. Select a location, type a name for your sequence, and click OK.
Note: If you capture 24p footage, Premiere Pro recognizes the footage as 24p and treats it accordingly, regardless of your sequence settings.
Set 24p playback options
You set playback settings when you create a new sequence.
1. Choose File > New >Sequence.
2. In the New Sequence dialog box, click the General tab.
3. Click Playback Settings.
4. In the 24p Conversion Method pane, select one of the following options:
Repeat Frame (ABBCD) Duplicates frames where necessary to maintain 29.97 fps playback. This option uses fewer CPU resources.
Interlaced Frame (2:3:3:2) Combines the frames in a telecine-like scheme to maintain 29.97 fps playback. This option produces smooth
playback but uses more CPU resources.
5. Click OK in the Playback Settings dialog box, and click OK in the New Sequence dialog box.
Disable 24p pulldown to simulate film-video transfer
By default, Premiere Pro uses a 24p pulldown scheme to play back 24p DV footage at 29.97 fps in a project based on one of the NTSC presets.
You can disable the pulldown scheme to give your movie the look of a film transferred to video or broadcast, without frame interpolation.
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