Adobe 25510629 - After Effects CS3 Professional, Руководство пользователя

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Fine-tuning the appearance of the video 111
Adding shadows and reflections
When done correctly, shadows and reflections provide a key finishing touch that helps sell the
illusion, melding the subject into the scene. When absent or done poorly, they can destroy the
compositing result. Ultra lets you generate up to three virtual shadows and a single reflection
on the floor and two shadows on the wall. In addition, Ultra provides the power to change
their position and appearance so that they’re always done correctly.
Creating realistic virtual shadows is not only in general much easier than trying to preserve the
input clip’s actual shadows, but also can produce better results. For more information, see
“Keeping the shadow in an input clip” on page 82 . In addition, if keeping the real shadow is
the only reason for using the Apply Points keying method, then choosing virtual shadows also
frees you to use the more advanced and effective Set Key method. For more information, see
“Multiple Key Points Method (Color Spread)” on page 80 and “Set Key” on page 78 .
Enabling a shadow or reflection and making it the active one
To turn each shadow or reflection on and off independently, select its check box.
Because a single set of controls on the Shadows tab serves both effects, a particular shadow or
reflection must be both enabled and selected as the active one before you can change it. If the
desired effect is disabled, then enabling it also makes it the active one. If it’s already enabled,
then you must click its name in the right column to select it as the active one. Selecting the
check box for an effect that’s already enabled selects it as the active one, but turns it off in the
process. If the sliders are dimmed, then the active effect is disabled.
In the following example, Shadow 1 and Shadow 3 are enabled, and Shadow 1 is active.