Adobe 25510629 - After Effects CS3 Professional, Руководство пользователя

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Creating and assigning sources and virtual sets 71
32 bit AVI with Alpha
4.
The clip is in the Output Clips folder, or the path that you set for it. Assign the clip to the
overlay as you would any source.
5.
Proceed with any resizing, repositioning, and so on.
Finished, composited scene
The following is an example of what the finished, composited scene looks like.
This example illustrates a common problem that ruins the illusion of the composited scene.
The subject’s toes are in a position where the overlay does not cover them. You have several
options for remedying the problem:
Include the area within the pink circle as part of the overlay image.
Use the Mask Painter to make that region of the input clip transparent. For more
information, see
“Cropping and spot masking the source clip” on page 83 .
Reposition the subject a few pixels to the left. For more information, see “Changing the
position and scale of a layer plane” on page 92 .
Depending on the scene and where the subject walks, you may also be able to use the
Input Cropping controls. For more information, see
“Cropping the edge of a frame”
on page 84 .
TI
P
If you’re working with a photographic image, a quick way to isolate the image with alpha
all around is to shoot it against a greenscreen and then delete that background in
Photoshop.
NO
T
E
If you want to have two or more objects in the foreground, you can put them in a single
image. Be aware, however, that they will move as a unit if you change their size, position,
or orientation.