User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
3 Select Conform to Frame Rate, and type a new frame rate in the Frames Per Second box.
Then click OK.
Note: This procedure can change the synchronization of audio and video files. Be sure to check
your files and make any necessary adjustments.
Using interlaced video in After Effects
If you want to use interlaced or field-rendered footage (such as from NTSC video) in an
After Effects project, you will get the best results if you separate the video fields when you
import the footage. After Effects separates video fields by creating a full frame from each
field, preserving all of the image data from the original footage.
When importing interlaced video that was originally transferred from film, you can remove
the 3:2 pulldown that was applied during the transfer from film to video as you separate
fields so that effects you apply in After Effects don’t appear distorted. See “Removing 3:2
pulldown from video transferred from film” on page 87.
Separating fields
Separating fields is critical if you plan to make significant changes to the footage. When
you scale, rotate, or apply effects to interlaced video, unwanted artifacts, such as crossed
fields, are often introduced. By separating fields, After Effects accurately converts the two
interlaced frames in the video to noninterlaced frames, while preserving the maximum
amount of image quality. Using noninterlaced frames allows After Effects to apply edits
and effects consistently and at the highest quality.
After Effects creates field-separated footage from a single formerly interlaced field by
splitting fields into two independent frames. Each new frame has only half the infor-
mation of the original frame, so some frames may appear to have a lower resolution than
others when viewed at Draft quality. When you render the final composition, After Effects
reproduces high-quality interlaced frames for videotape. When you render a movie at Best
quality, After Effects interpolates between the scan lines of a field to produce maximum
image quality.
Note: After Effects automatically separates fields for D1 and DV video footage files. You can
manually separate fields for all other types of video footage in the Interpret Footage dialog box.
For more information, see “Specifying interpretation rules” on page 67.
UG.book Page 85 Wednesday, February 21, 2001 12:05 PM