Apple Shake 4 - Manual (Page 782)

782 Chapter 26 Transformations, Motion Blur, and AutoAlign
The following example uses a previously rendered a clip of a swinging pendulum.
To add blur to a non-animated object with the useReference parameter:
1 Locate the center of rotation for the pendulum, then type the center values in the
Move2D center field.
2 Approximate the rotation, then animate the angle to match the rotation.
In this example, the angle is -40 at frame 5 and 40 at frame 24.
3 Type the expression “time” into the referenceFrame value field (in the useReference
subtree).
4 Set motionBlur to 1.
When the animation is played back, the entire element swings out of frame due to the
new animation.
5 Enable useReference (set it to 1).