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Animation basics About animation, keyframes, and expressions Animation is change over time. You animate a layer or an effect on a layer by changing one or more of its properties over time. For example, you can animate a layer’s Opacity property from 0% to 100% to make the layer fade in. Any property with a stopwatch button to the left of its name in the Timeline panel or Effect Controls panel can be animated.
A B Stopwatch icons A. Active stopwatch B. Inactive stopwatch You animate layer properties using keyframes, expressions, or both.
To see a video tutorial on animating using keyframes, visit the Adobe website at www.adobe.com/go/vid0227.
Some tools, such as Motion Sketch and the Puppet tools, automatically set keyframes for you to match motion that you sketch.
Many animation presets include keyframes and expressions so that you can simply apply the animation preset to the layer to achieve a complex animated result.
You work with keyframes and expressions in After Effects in one of two modes: layer bar mode or Graph Editor mode.
Layer bar mode is the default, which shows layers as duration bars, with keyframes and expressions aligned vertically with their properties in the Timeline panel. Graph Editor mode does not show layer bars, and shows keyframes and expression results in value graphs or speed graphs. (See “Work with the Graph Editor” on page 184.)
When the stopwatch is active for a specific property, After Effects automatically sets or changes a keyframe for the property at the current time whenever you change property value. When the stopwatch is inactive for a property, the property has no keyframes. If you change the value for a layer property while the stopwatch is inactive, the value remains in effect for the duration of the layer.
If you deselect the stopwatch, all keyframes for that layer property are deleted, and the constant value for the property becomes the value at the current time. Don’t deselect the stopwatch unless you’re sure that you want to permanently delete all of the keyframes for that property.
Change the keyframe icons in layer bar mode to numbers by choosing Use Keyframe Indices in the Timeline panel menu.
Keyframes as icons compared to keyframes as numbers
Before you make any changes to a keyframe, make sure that the current-time indicator is positioned at an existing keyframe. If you change a property value when the current-time indicator is not at an existing keyframe, After Effects adds a new keyframe. However, if you double-click a keyframe to modify it, the current-time indicator location is not relevant, nor is it relevant when you change a keyframe’s interpolation method.
See also “Interpolation” on page 204 “About animation presets” on page 347 “Shortcuts for keyframes” on page 650
Two animated properties (Position and Scale) shown in the Graph Editor There are two types of graphs available in the Graph Editor: value graphs, which show property values; and speed graphs, which show rates of change of property values. For temporal properties, such as Opacity, the Graph Editor defaults to the value graph. For spatial properties, After Effects defaults to the speed graph.
In the Graph Editor, each property is represented by its own curve. You can view and work on one property at a time, or you can view multiple properties simultaneously. When more than one property is visible in the Graph Editor, each property’s curve has the same color as the property’s value in the layer outline.
When you drag a keyframe in the Graph editor with the Snap button selected, the keyframe snaps to keyframe values, keyframe times, the current time, In and Out points, markers, the beginning and end of the work area, and the beginning and end of the composition. When the keyframe snaps to one of these items, an orange line appears in the Graph Editor to indicate the object you’re snapping to. Hold Ctrl (Windows) or Command (Mac OS) after you’ve begun dragging to temporarily toggle snapping behavior.
Keyframes in Graph Editor mode may have direction handles attached to one or both sides. Direction handles are used to control Bezier interpolation.
Keyframes in the Graph Editor with direction handles See also “Interpolation” on page 204 “About speed graphs” on page 210 Select which properties are shown in the Graph Editor ❖ Click the Show Properties button at the bottom of the Graph Editor, and select from the following options:
Show Selected Properties Displays selected properties in the Graph Editor.
Show Animated Properties Displays animated properties of selected layers in the Graph Editor.
Graph Options in the Graph Editor
Click the Graph Options button at the bottom of the Graph Editor to select from the following options:
Auto-Select Graph Type Automatically selects the appropriate graph type for a property: speed graphs for spatial properties (such as Position), and value graphs for other properties.
Edit Value Graph Displays the value graph for all properties.
Edit Speed Graph Displays the speed graph for all properties.
Show Reference Graph Displays the unselected graph type in the background for viewing only. (The gray numbers to the right of the Graph Editor indicate the values for the reference graph.) Show Audio Waveforms Displays the audio waveform for any layer that has at least one property in the Graph Editor.
Show Layer In/Out Points Displays In and Out points of all layers that have a property in the Graph Editor.
Show Layer Markers Displays layer-time markers in the Graph Editor, if they exist.
Show Graph Tool Tips Toggles the graph tool tips on and off.
Show Expression Editor Shows or hides the expression editor field.
Allow Keyframes Between Frames Allows placement of keyframes between frames for fine tuning animation.
Pan and zoom in the Graph Editor
• To pan vertically or horizontally, drag with the Hand tool.
To activate the Hand tool momentarily when using another tool, press and hold the spacebar.
• To pan vertically, spin the mouse scroll wheel.
• To pan horizontally, press the Shift key as you spin the mouse scroll wheel.
• To zoom in, click with the Zoom tool.
• To zoom out, Alt-click (Windows) or Option-click (Mac OS) with the Zoom tool.
• To zoom using the mouse scroll wheel, press Alt (Windows) or Option (Mac OS) while scrolling to zoom horizontally; press Ctrl (Windows) or Command (Mac OS) to zoom vertically.
• To zoom horizontally, Alt-drag (Windows) or Option-drag to the left with the Zoom tool to zoom out or to the right to zoom in.
• To zoom vertically, Alt-drag (Windows) or Option-drag up with the Zoom tool to zoom in or down to zoom out.
Note: You cannot pan or zoom vertically when Auto Zoom Height is selected.
Setting, selecting, and deleting keyframes Set keyframes When the stopwatch is active for a specific property, After Effects automatically adds or changes a keyframe for the property at the current time whenever you change the property value.
1 Move the current-time indicator to the time where you want to begin the animation.
2 Set the layer property to the value you want at that point in time; for example, move the layer to a new position.
3 Do one of the following:
• Click the Stopwatch icon next to the property name to activate it. After Effects creates a keyframe at the current time for that property value.
• Choose Animation Add [x] Keyframe, where [x] is the name of the property you are animating.
4 Move the current-time indicator to the time where you want to add an additional keyframe.
5 Change the value for the property in the layer outline.
6 Repeat steps 4 and 5 as many times as you want to add more keyframes.
See also “About animation, keyframes, and expressions” on page 183 “Shortcuts for keyframes” on page 650 “Move the current-time indicator” on page 123 “Shortcuts for showing properties in the Timeline panel” on page 647 Add a keyframe without changing a value 1 In the Timeline panel, select the layer that you want to animate.
2 Show the layer property for which you want to add a keyframe. The property must already contain at least one keyframe.
3 Move the current-time indicator to the point where you want to add a new keyframe. If the current-time indicator is after the last keyframe for that layer property, the new keyframe will have the same value as the preceding keyframe. Otherwise, the new keyframe’s value will be an interpolated value based on the previous and next keyframe values.
4 Do one of the following:
• Click the keyframe navigator button for the layer property.
• Choose Animation Add [x] Keyframe, where [x] is the name of the property you are animating.
• Click on a segment of the layer property’s graph in the Graph Editor with the Pen tool.
“Shortcuts for keyframes” on page 650 “Shortcuts for showing properties in the Timeline panel” on page 647 Move the current-time indicator to a keyframe After you set the initial keyframe for a property, After Effects displays the keyframe navigator, which you can use to move from keyframe to keyframe or to set or remove keyframes. When the keyframe navigator box is filled with a yellow diamond, the current-time indicator lies precisely at a keyframe for that layer property. When the keyframe navigator box is not filled, the current-time indicator lies between keyframes.
To detach the keyframe navigator from the A/V Features column to function as its own column, choose Column Keys from the Timeline panel menu.
A B C Keyframe navigator in Timeline panel A. Keyframe at current time B. No keyframe at current time C. No keyframes for layer property
• To move to the next or previous keyframe, click a keyframe navigator arrow.
• To snap to a keyframe or marker, Shift-drag the current-time indicator.
• To move to the next or previous visible item in the time ruler (keyframe, marker, or work area end), press K or J.
See also “About animation, keyframes, and expressions” on page 183 “Work with the Graph Editor” on page 184 Select keyframes In layer bar mode, selected keyframes are yellow. Unselected keyframes are gray.
In Graph Editor mode, the appearance of a keyframe icon depends on whether the keyframe is selected, unselected, or semi-selected (another keyframe in the same property is selected). Selected keyframes are solid yellow. Unselected keyframes retain the color of their corresponding graph. Semi-selected keyframes are represented by a hollow yellow box.
• To select a keyframe, click the keyframe icon.
• To select multiple keyframes, Shift-click the keyframes or drag a marquee around the keyframes.
Note: To toggle viewing of the free-transform bounding box in the Graph Editor, click the Show Transform Box button at the bottom of the Graph Editor.
• To select all keyframes for a layer property, Alt-click (Windows) or Option-click (Mac OS) a segment between two keyframes in the Graph Editor, or click the layer property name in the layer outline.
• To select all keyframes for a property that have the same value, right-click (Windows) or Control-click (Mac OS) a keyframe, and choose Select Equal Keyframes.
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• To select all keyframes that follow or precede a selected keyframe, right-click (Windows) or Control-click (Mac OS) a keyframe, and choose Select Previous Keyframes or Select Following Keyframes.
Note: The Select Previous/Following Keyframes commands aren’t available if more than one keyframe is selected.
See also “About animation, keyframes, and expressions” on page 183 “Work with the Graph Editor” on page 184 “Shortcuts for keyframes” on page 650 “Shortcuts for showing properties in the Timeline panel” on page 647 Keyframe menu commands When you select one or more keyframes, the keyframe menu becomes available at the bottom of the Graph Editor.
To open the keyframe menu, right-click (Windows) or Control-click (Mac OS) a keyframe.
[Value] Displays the value of the selected keyframe. If more than one keyframe is selected, the Display Value command is available, which displays the value of the highlighted keyframe in the selection.
Edit Value Opens a dialog box in which you can edit the value of the keyframe.
Select Equal Keyframes Selects all keyframes in a property that have the same value.
Select Previous Keyframes Selects all keyframes preceding the currently selected keyframe.
Select Following Keyframes Selects all keyframes following the currently selected keyframe.
Toggle Hold Keyframe Holds the property value at the value of the current keyframe until the next keyframe is reached.
Keyframe Interpolation Opens the Keyframe Interpolation dialog box.
Rove Across Time Toggles Rove Across Time for spatial properties.
Keyframe Velocity Opens the Keyframe Velocity dialog box.
Keyframe Assistant Opens a submenu with the following options:
• Time-Reverse Keyframes Reverses selected keyframes in time.
See also “Interpolation” on page 204 Delete or disable keyframes
• To delete any number of keyframes, select them, and then press the Delete key.
• To delete one keyframe in the Graph Editor, Ctrl-click (Windows) or Command-click (Mac OS) a keyframe with the Selection tool.
• To delete all keyframes for one layer property, click the stopwatch button to the left of the name of the layer property to deactivate it.