User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
Substituting a placeholder for footage
A placeholder appears in After Effects as a still image of color bars. You can apply a mask,
effects, and geometric properties to a placeholder. When the actual footage item becomes
available, you can replace the placeholder with it, and the applied attributes and keyframes
are transferred to the actual footage.
For best results, set the placeholder to exactly the same size, duration, and frame rate as
the actual footage.
To use a placeholder:
1 Choose File > Import > Placeholder or File > Replace Footage > Placeholder.
2 In the New Placeholder dialog box that appears, specify the placeholder’s name, size,
frame rate, and duration, and then click OK.
To replace a placeholder with the actual footage:
1 In the Project window, double-click the placeholder you want to replace.
2 Locate and select the actual footage, and then click OK, or choose File > Replace
Footage > File to locate the file.
Substituting a low-resolution proxy for footage
Movies, images, and compositions used as layers can take up significant amounts of RAM
and disk space when used in compositions, and can slow down working and rendering in
elaborate projects. Using low-resolution proxy items in place of actual items is a way to
lighten the burden on your computer and speed your work. Effects, masks, and properties
applied to the proxy are applied to the actual footage item when you replace the proxy with
the actual footage.
When you use a proxy, After Effects replaces the actual footage with the proxy in all
compositions that use the actual footage item. When you finish working, you can switch
back to the actual footage item in the project list. After Effects then replaces the proxy with
the actual footage item in any composition.
When you render your composition as a movie, you may choose to use either all the actual
high-resolution footage items or their proxies. You might want to use the proxies for a
rendered movie if, for example, you simply want to test motion using a rough movie that
renders quickly.
UG.book Page 99 Wednesday, February 21, 2001 12:05 PM