User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
5 Select a Quality level from Least to Best.
Note (Mac OS Only): If you intend to use key frames in the movie, hold down Option and
adjust the Quality slider to control the temporal compression of the movie. Temporal
compression compresses a movie by comparing successive frames and keeping only changed
data. High temporal quality maintains smoothness of motion. Low temporal quality tends to
produce jerkiness of motion because a pixel doesn’t change unless the difference between
frames is great.
6 If you want the smallest possible files, and your compressor choice allows for a key frame
rate, select the box and type a number in the Key Frame Every box. Generally, you should
type a number equal to the frame rate. For example, if you set a frame rate of 30 fps, type 30
in the Key Frame box. This sets one key frame every 30 frames of your movie.
Note: If you are going to use the resulting movie in another After Effects composition, type a
small value (less than 5) in the Key Frame Every box or deselect the Key Frame Every option.
The presence of key frames greatly increases the memory required to edit and render a movie.
7 Click OK.
8 If your compressor choice supports different image color depths, choose the appro-
priate color depth in the Output Module Settings dialog box:
• Choose Millions of Colors+ if you want 24-bit color quality and you want your compo-
sition background to be transparent (to include an alpha channel). The composition’s
background color is disregarded. Only Animation and None can support the Millions of
Colors+ color depth.
• Choose Millions of Colors if you want 24-bit color quality but want to include your
composition background color (no alpha channel).
Note: Color depth settings of Thousands of Colors or lower may cause banding and dithered
images.
9 Choose other options in the Output Module Settings dialog box, as described in
“Changing output module settings” on page 361. Then click OK.
Setting Video for Windows compression options
When setting Video for Windows compression options, you can specify the compressor
and compression quality. Compressors available for Video for Windows include Microsoft
Video 1, Cinepak, Microsoft RLE, Microsoft DV, and Intel Video. Choose a compressor
based on the type of original images you have and the purpose of the rendered movie:
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