Before you change 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 the interpolation method of a keyframe.
Jeff Almasol provides a script on his redefinery website that creates new layer markers (either on the selected layer or on a new null layer) with comments that provide information about keyframes at the same times.
You can copy keyframes from only one layer at a time. When you paste keyframes into another layer, they appear in the corresponding property in the destination layer. The earliest keyframe appears at the current time, and the other keyframes follow in relative order. The keyframes remain selected after pasting, so you can immediately move them in the destination layer.
You can copy keyframes between layers for the same property (such as Position) or between different properties that use the same type of data (such as between Position and Anchor Point).
When copying and pasting between the same properties, you can copy from more than one property to more than one property at a time. However, when copying and pasting to different properties, you can copy only from one property to one property at a time.
To paste to the same property of the copied keyframes, select the destination layer.
To paste to a different property, select the destination property.
You can copy and paste keyframe data as tab-delimited text for use in a spreadsheet program (such as Microsoft Excel) or other text-editing program. You can use a spreadsheet program to perform numerical analysis on keyframe data or create or edit keyframe values.
You can copy and paste most properties, including the Transform properties (such as Position and Opacity), Material Options properties, and motion trackers.
You can use the motion tracking tools to track the motion of an object in a layer, and then paste the tracker data into a spreadsheet to perform numerical analysis on the data.
Some utility applications, such as Imagineer Systems mocha for After Effects (mocha-AE), copy keyframe data to the clipboard so that you can paste it into the appropriate layer in After Effects.
You can copy keyframes from only one layer at a time as tab-delimited text.
Place a composition marker at the time of the first selected keyframe so that you will know where to paste the modified keyframes in the last step. (See Layer markers and composition markers.)
Select the cells that contain your data. The upper-left cell in your selection should be A1. The bottom row of your selection should be the row that contains the text End of Keyframe Data.
You can move keyframes in time, either individually or as a group.
Jeff Almasol provides a versatile script on his redefinery website that creates a panel with controls for moving various combinations of items in time—layer In point, layer Out point, layer source frames, keyframes, and markers.
With multiple keyframes selected, you can copy or delete them simultaneously or move the keyframes together without changing their positions relative to each other.
You can also move selected keyframes in time (one frame earlier or later) by pressing the Alt (Windows) or Option (Mac OS) key with the left arrow or right arrow key.
In layer bar mode, hold down Shift after you begin to drag a keyframe icon to the current-time indicator.
In Graph Editor mode, drag a keyframe to the current-time indicator.
When you drag over the current-time indicator, the keyframe snaps to the current-time indicator.
You can change the values of multiple keyframes on multiple layers at one time; however, all keyframes you select must belong to the same layer property. The way the selected values change depends on the method you use to make the change:
If you change a value numerically, all selected keyframes use the new value exactly. In other words, you make an absolute change. For example, if you select several Position keyframes on a motion path and numerically specify a Position value for one of them, all selected keyframes change to the same position value.
If you change a value by dragging the underlined value, all selected keyframes change by the same amount. In other words, you make a relative change. For example, if you select several Position keyframes on a motion path and drag the underlined value for one of them, all selected keyframe values change by the same amount.
If you change a value graphically in the Composition or Layer panel, all selected keyframes change using the difference between the old and new values, not the values themselves. In other words, you make a relative change. For example, if you select several Position keyframes on a motion path and then drag one of them 10 pixels to the left, they all move 10 pixels to the left of their original positions.
You can also change the value of several layers at once in layer bar mode by parenting them.
Mathias Möhl provides the KeyTweak script (available on the After Effects Extension page), with which you can modify many keyframes on a property simultaneously. With KeyTweak, you can modify a few keyframes manually, and the script modifies the remaining keyframes in between accordingly. KeyTweak is especially useful for Mask Path keyframes in a rotoscoping workflow. (See Rotoscoping introduction and resources.)
A value graph in the Graph Editor displays the values for each keyframe and the interpolated values between keyframes. When the value graph of a layer property is level, the value of the property is unchanged between keyframes. When the value graph goes up or down, the value of a layer property increases or decreases between keyframes.
A. Keyframe. B. A level value graph indicates unchanging values. C. A rising graph indicates increasing values. D. A falling graph indicates decreasing values.
You can change layer property values by moving the points (keyframes) on the value graph up or down. For example, you can increase the value of a Rotation keyframe by dragging the keyframe marker on the Rotation property’s value graph higher up on the graph.
Values for the Anchor Point, Mask Path, effect control points, 3D Orientation, and Position properties are spatial, so they use speed graphs by default instead of value graphs.
You can edit and move multiple keyframes simultaneously using the Graph Editor. When you select multiple keyframes with the Show Transform Box button selected, a free-transform bounding box surrounds the selected keyframes, and an anchor point appears in the center of the bounding box to mark the center point for the transformation. You can move the selected keyframes in time or value by dragging the bounding box or its handles. You can also change the position of the anchor point.
Adjusting a free-transform bounding box in a value graph moves the selected keyframes in time and value. Adjusting a free-transform bounding box in a speed graph moves the selected keyframes in time only.
To select keyframes, Shift-click the keyframes or drag to draw a marquee around the keyframes.
To select all keyframes for a property, Alt-click (Windows) or Option-click (Mac OS) a segment between two keyframes.
To move keyframes in time or value, place the pointer inside the bounding box and drag. Shift-drag to constrain the move horizontally or vertically.
To move keyframes in time or value by scaling the bounding box, place the pointer on a bounding box handle. When the pointer changes to a straight, double-sided arrow , drag the bounding box to a new size. Shift-drag to constrain the ratio of width to height. Ctrl-drag (Windows) or Command-drag (Mac OS) to scale around the anchor point of the bounding box. When dragging a corner handle, Alt-drag (Windows) or Option-drag (Mac OS) to move only that handle.
Scale by negative amounts to reverse the keyframes in time.
To taper keyframe values vertically, Ctrl+Alt-drag (Windows) or Command+Option-drag (Mac OS). Tapering keyframe values allows you to reduce or expand the amplitude of a repeated animation.
To move one side of the bounding box up or down, Ctrl+Alt+Shift-drag (Windows) or Command+Option+Shift-drag (Mac OS).
To move the anchor point of the bounding box, place the Selection tool over the anchor point until the tool changes to the Move Anchor Point tool , and then drag.