Adobe 12040118 - After Effects Standard, Руководство

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For more precision in setting audio levels by dragging sliders, increase the height of the Audio panel.
In the Audio panel, to adjust volume, do one of the following:
To set the level of the left and right channels together, drag the center slider up or down.
To set the level of the left channel, drag the left slider up or down, or type a new value in the levels box at the bottom of the left slider.
To set the level of the right channel, drag the right slider up or down, or type a new value in the levels box at the bottom of the right slider.
Parent and child layers
To synchronize changes to layers by assigning one layer’s transformations to another layer, use parenting. After a layer is made a parent to
another layer, the other layer is called the child layer. When you assign a parent, the transform properties of the child layer become relative to the
parent layer instead of to the composition. For example, if a parent layer moves 5 pixels to the right of its starting position, then the child layer also
moves 5 pixels to the right of its position. Parenting is similar to grouping; transformations made to the group are relative to the anchor point of the
parent.
Parenting affects all transform properties except Opacity: Position, Scale, Rotation, and (for 3D layers) Orientation.
Note: When parenting layers in After Effects CS6, helpful text describing alternate parenting behaviors is displayed on the layer bar below the
mouse position and in the Info panel.
A layer can have only one parent, but a layer can be a parent to any number of layers in the same composition.
You can animate child layers independent of their parent layers. You can also parent using null objects, which are hidden layers.
You cannot animate the act of assigning and removing the parent designation—that is, you cannot designate a layer as a parent at one point in
time and designate it as a normal layer at a different point in time.
When you create a parenting relationship, you can choose whether to have the child take on the transform property values of the parent or retain
its own. If you choose to have the child take on the transform property values of the parent, the child layer jumps to the parent’s position. If you
choose to have the child retain its own transform property values, then the child stays where it is. In both cases, subsequent changes to the
transform property values of the parent are applied to the child. Similarly, you can choose whether the child jumps when the parenting relationship
is removed.
Note: In After Effects CS6, when parenting layers, you can use the Shift key to move the child layer to the location of the parent. This can be
useful when you want to attach a layer to a null, but have the layer move to the location of the parent null (for example, attaching a 3D text layer to
a null layer created from the 3D Camera Tracker).
Dragging the pick whip in the Timeline panel to designate the planet layer as the parent to the saucer layer
Note: To show or hide the Parent column in the Timeline panel, choose Columns > Parent from the Timeline panel menu.
To parent a layer, in the Parent column, drag the pick whip from the layer that is to be the child layer to the layer that is to be the parent
layer.
To parent a layer, in the Parent column, click the menu of the layer that you want to be the child, and choose a parent layer name from the
menu.
To remove a parent from a layer, in the Parent column, click the menu of the layer to remove the parent from, and choose None.
To extend the selection to include all child layers of a selected parent layer, right-click (Windows) or Control-click (Mac OS) the layer in the
Composition or Timeline panel, and choose Select Children.
To make a child layer jump when a parent is assigned or removed, hold down Alt (Windows) or Option (Mac OS) as you assign or remove
the parent.
To remove a parent from a layer (that is, set Parent to None), Ctrl-click (Windows) or Command-click (Mac OS) the parenting pick whip of
the child layer in the Timeline panel. Alt+Ctrl-click (Windows) or Command-click (Mac OS) the parenting pick whip of the child layer
to remove the parent and cause the child layer to jump.
Online resources about parent and child layers
Paul Tuersley provides a script on the AE Enhancers forum for duplicating a parent layer and all of its children, preserving the parenting hierarchy.
Angie Taylor provides a character animation tutorial on her Creative After Effects website that shows how to use parenting and expressions. Angie
provides a more extensive discussion and explanation of animation using parenting, expressions, and null object layers in a PDF excerpt from her
book
Creative After Effects 7: Workflow Techniques for Animation, Visual Effects, and Motion Graphics .
Trish and Chris Meyer provide an introduction to parenting in a PDF excerpt from the “Parenting and Nesting” chapter of their book After Effects
Apprentice: Real-World Skills for the Aspiring Motion Graphics Artist .
Guy Chen provides a simple project on the After Effects Exchange on the Adobe website that demonstrates the animation of several 3D layers
arranged as a cube, controlled by a parent null layer.