Using the reverse telecine and conform features, Converting ntsc edls to 24 fps – Apple Cinema Tools 4 User Manual
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For offline editing, it is preferred that the 24p video be compressed and captured directly,
with no frame rate conversions. This removes the possibility of errors during video and
timecode rate conversions and eliminates the need to convert the video’s aspect ratio
(see
). However, this requires specialized hardware, so the
following alternatives using standard downconverted versions of the 24p video have
been developed.
Using the Reverse Telecine and Conform Features
24p video is often downconverted to make it easier to use with standard video equipment.
Cinema Tools provides tools to convert NTSC or PAL captured clips back to their original
24 fps video, enabling you to edit using a 24 fps timebase:
• NTSC: Converting 24p video to NTSC video requires using a pull-down method that
adds redundant fields, maintaining the action’s original speed (1 second of 24p video
equals 1 second of NTSC video). The Reverse Telecine feature removes the pull-down
by removing the extra fields and restores the original 24 fps rate. See
for information about using the Reverse Telecine feature. If your
source clips originated from a special type of DV camcorder that shoots 24p, such as
the Panasonic AG-DVX100 camcorder, a simpler form of the Reverse Telecine dialog
appears. See
Removing 2:3:3:2 or 2:3:2:3 Pull-Down with Cinema Tools
for information
about reversing the pull-down for clips that originated from a 24p-capable digital video
camcorder.
• PAL: There are several methods of converting 24p video to PAL. The most common is
to play the tape 4 percent faster, providing a one-to-one relationship between the 24p
and PAL frames, but speeding up the action by 4 percent. Cinema Tools and Final Cut Pro
provide a Conform feature that you can use to restore the video back to 24 fps in order
to edit it at 24 fps in Final Cut Pro. See
for information about frame
rate issues.
Converting NTSC EDLs to 24 fps
You may decide to edit the downconverted NTSC version of the 24p video using a standard
NTSC 29.97 fps timebase; however, most 24p online editing systems require a 23.98 fps
or 24 fps EDL.
Cinema Tools includes a feature that allows you to convert NTSC 29.97 fps EDLs to 23.98 fps
or 24 fps. This makes it possible for you to perform an offline edit of your downconverted
24p video on an NTSC system and export an EDL that can be converted and used by an
online system.
Note: Cinema Tools does not support converting PAL EDLs to 24 fps.
To convert an NTSC EDL to 24 fps, you need the EDL file to be converted in the CMX 3600
or GVG format. You do not need a Cinema Tools database.
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Chapter 13
Working with 24p Video and 24 fps EDLs