Controlling Keyframes

At this stage in the chapter you should now understand how keyframes can enhance and customize your own filters. But you must carefully control keyframes if you're to get the best from them.

In this section, you learn how to manually add and delete a keyframe and how to copy/paste and move a keyframe inside the Filter Editor.

To add a keyframe

1.	With the editor open, scrub through the Timeline until you find the spot where you want to add a keyframe.
2.	When the cursor is over this spot, click the Set Keyframe button .

To delete a keyframe

1.	With the editor open, scrub through the Timeline until you are on a keyframe, or use the Go to Next Keyframe buttons to find each keyframe.
2.	When the cursor is over the keyframe, the Delete Keyframe button becomes active. Click it and the keyframe vanishes.

To copy and paste a keyframe

1.	Place a keyframe anywhere on the Timeline using the methods detailed above.
2.	With the cursor over the keyframe, click the copy Keyframe button .
3.	Move the cursor to the new point by scrubbing or playing, then click the Paste Keyframe button to apply this keyframe.

Tip

• The keyframes copied in the manner described above are entirely independent of their original keyframes and vice versa. Altering one doesn't change the other.

To move a keyframe

• Hold down the Alt key, then, using the mouse, left-click the keyframe and drag it to the new position. Note: the last keyframe cannot be moved.
  
  

Deactivating a keyframe area

Occasionally you may want to turn off certain parameters to see the interaction of the other keyframes on the Timeline more clearly. You can accomplish this using the Keyframe toggle.

To deactivate a set of keyframes

• Click the Activate square at the end of the row.
  
  It turns from gold to blue and the parameters become grayed out (Figure 9.43).
  
  

  Figure 9.43. Deactivating a keyframe range.

  

  
  If you scrub through this effect window, these keyframes won't be used.
  
  

Reversing Keyframes

One button common to both the RT and Classic interfaces is the Revert Direction of Effect button , which inverts the keyframes you've created, effectively playing the filter backward.

Due to technical restrictions, not all filters have this button.