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Time display units
Many
quantities in After Effects are either points in time or spans of
time, including the current time, layer In and Out points, and durations
of layers, footage items, and compositions.
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 frames, or feet and frames of 16mm or 35mm film.
Video-editing
workstations often use SMPTE timecode that is recorded 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.
You
may want to see time values in feet plus frames format, for example,
if you are preparing a movie for eventual output to film; or in
simple frame numbers if you plan to use your movie in an animation
program such as Flash. The format you choose applies to the current
project only.
Important: Changing the time display
format does not alter the frame rate of your assets or output—it
changes only how frames are numbered for display in After Effects.
Change time-display units- To
cycle through Timecode Base, Frames, and Feet + Frames, Ctrl-click (Windows)
or Command-click (Mac OS) the current-time display. The current-time
display is in the upper-left corner of the Timeline panel and at
the bottom of the Layer, Composition, and Footage panels. (See Timeline panel.)
- To change time display units, choose File >
Project Settings, and choose from the options in the Display Style
section.
Options for time-display units- Timecode Base
- Displays time as timecode, using the frame rate that you
specify as the timecode base. Auto uses the rounded frame rate of
the footage item or composition. If an item doesn’t have timecode
(such as an audio file), After Effects uses a default value (30
fps for English, Japanese, and Korean versions of After Effects,
or 25 fps for French, German, Spanish, and Italian versions) or
the last non-auto value you specified in the Project Settings dialog
box. You can also specify that After Effects use a specific frame
rate.
Note: You can specify specific frame rates for
display in the Timecode Base menu; however, in most cases, you should
leave the timecode base set to Auto.
- Drop Frame versus Non-Drop Frame
- Two of the more commonly used combinations of time display
settings are 30 fps drop-frame timecode and 30 fps non-drop-frame
timecode. When the frame rate is a non-integer number—as is the case
with the NTSC frame rate of 29.97 frames per second—a compromise
of one sort or another must be made in displaying time. Either the
time display can accurately show clock time (after one hour, the
time display shows 1:00:00:00) or the time display can be continuously
numbered (frame n is always followed by frame n +
1, modulo the number of frames per second). Drop-frame timecode does
the former; non-drop-frame timecode does the latter. In the case
of NTSC 30 fps drop-frame timecode, two frame numbers are skipped
for each minute, except for every tenth minute. Drop-frame timecode
is conventionally indicated by separating the time units with semicolons.
The most common case for which drop-frame versus non-drop-frame
timecode is relevant is 29.97 fps NTSC, but it also applies to 23.976
fps (which After Effects treats as non-drop-frame timecode) and
59.94 fps.
Timecode for 59.94 fps compositions and footage
items matches that in Adobe Premiere Pro: When the timecode base
is 30 fps, each timecode value repeats twice. When the timecode
base is 60 fps drop-frame, frame numbers 0, 1, 2, and 3 are dropped
in the same places as where 0 and 1 are dropped for drop-frame timecode
with a timecode base of 30 fps.
- Feet + Frames
- Displays number of feet of film, plus frames for fractional
feet, for 16mm or 35mm film. Numbering starts at the frame number
that you specify with the Start Numbering Frames At value.
- Frames
- Displays frame number instead of time. Use this setting for
convenience when doing work that you are integrating with a frame-based
application or format, like Flash or SWF.
Online resources about timecode
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