User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
For a list of common extensions and their associated file types, see the Adobe Web
site.
Resources Ensure that all resources are available on both systems. Resources can include
fonts, effects, and compressors.
Time basics
Time is central to many operations in After Effects. You can view, specify, and manage time
in various ways. Whichever way you handle time, there are several specific time concepts
you should understand as you create a project.
Time display
The way you view and specify time in After Effects depends on the display style, or unit of
measure, that you use to describe time. By default, After Effects displays time in Society of
Motion Picture and Television Engineers (SMPTE) timecode: hours, minutes, seconds,
and frames. You can change to another system of time display, such as film frames, or feet
and frames of 16mm or 35mm film. See “Setting time-display options” on page 42.
Video-editing workstations use SMPTE timecode that is often striped (encoded) onto
videotape for reference. If you are creating video that will be synchronized with video that
uses SMPTE timecode, use the default timecode display style.
Frame rate
Each composition you create can have its own frame rate. The frame rate is the number of
frames the rendered composition produces in every second when played back. The frame
rate you use is generally determined by the type of output you will produce. For example,
video for NTSC television plays at 29.97 frames per second (fps), and PAL plays at 25 fps.
When you set up changes over time, After Effects treats the changes as continuous
throughout a composition timeline. Each frame is rendered as a slice out of the timeline
at the frame rate you specify. Because After Effects treats time continuously, it is possible
to change a composition’s frame rate at any time or override the frame rate of a compo-
sition when you render the final movie. See “Setting frame rate” on page 105.
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