Adobe 25510629 - After Effects CS3 Professional, Руководство пользователя

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108 How to
Matching mixed media: If the input clips are DV that were compressed, but the
background was shot on film, the two sources may not match perfectly. Typically, the film
footage looks too clean compared to the subject. Since there’s no way to make the DV clip
as clean as the film, you can compress the film clip in an NLE, such as Premiere Pro, using
the same codec, or you can add noise using Adobe Premiere Pro.
Matching the audio to the virtual environment: In some situations, you may want to
process the audio for a composited scene to make it sound like it was recorded in an
environment similar to the virtual set in which the scene takes place. For example, if a
scene is set in a large virtual cathedral, you may want to add some reverb to the actor’s
voice. You can also change the reverb and equalizer settings to simulate relative
microphone distance between tight shots and wide shots. You may also want to mix in
subtle appropriate ambient sound effects, such as street noise or wind in the trees. You
cannot change the audio in Ultra. You can use an application such as Adobe Audition or
Soundbooth.
Correcting colors
Ultra lets you adjust the colors of any source in a session. For the input clip, you can make
separate adjustments for pre-processing and post-processing. Changes made in the Pre-
Processing mode are applied to the source before being keyed and, therefore, affect what the
keyer sees and has to work with. Post-Processing adjustments are applied after keying. If the
color of the background is not well-saturated and, therefore, is not keying well, then you may
want to change them in the Pre-Processing mode. If the keyed subject does not fit in well with
the selected virtual set or requires corrections to counter pre-processing color adjustments,
then you may want to adjust its colors in the Post-Processing mode. To select the appropriate
mode, select its option at the top of the control area. The controls in these modes are identical
with the exception of the Gamma slider, which is available only in the Post-Processing mode.