AfterEffects

Add randomness to a property with The Wiggler

You can add randomness to any property as it varies over time by using The Wiggler. You can also use the wiggle expression to accomplish this. (See Property attributes and methods.) Depending on the property and the options you specify, The Wiggler adds a certain number of deviations to a property by adding keyframes and randomizing interpolations coming into or out of existing keyframes. You need at least two keyframes to use The Wiggler.

Using The Wiggler, you can more closely simulate natural movement within specified limits. For example, add randomness to an animated butterfly to produce fluttering. Add it to brightness or opacity to simulate the flicker of an old projector.

  1. Select a range of keyframes for the property.
  2. Choose Window > The Wiggler.
  3. For Apply To, select the type of curve you want The Wiggler to change. If you selected keyframes for a property that varies spatially, you can select Spatial Path to add deviations to the motion, or Temporal Graph to add deviations to the velocity. If you selected keyframes for a property that does not vary spatially, you can select only Temporal Graph.
  4. Select a Noise Type option to specify the type of deviation due to randomly distributed pixel values (noise):
    Smooth Noise
    Produces deviations that occur more gradually, without sudden changes.

    Jagged Noise
    Produces sudden changes.

  5. Select the dimensions of the property you want to affect:
    One Dimension
    Adds deviations to only one dimension of the selected property. Choose the dimension from the menu.

    All Dimensions
    Independently adds a different set of deviations to each dimension.

    All Dimensions The Same
    Adds the same set of deviations to all dimensions.

  6. Set Frequency to specify how many deviations (keyframes) per second After Effects adds to the selected keyframes. A low value produces only occasional deviations, while a high value produces more erratic results. A value between 0 and 1 creates keyframes at intervals of less than one per second. For example, a value of 0.5 creates one keyframe every 2 seconds.
  7. Set Magnitude to specify the maximum size of the deviations. After Effects sets the specified magnitude to the units of the selected property, so a value for one property may produce very different results in another property.
  8. Click Apply and preview the results.
  9. If necessary, choose Edit > Undo The Wiggler to reset the keyframes, adjust the values for Frequency and Magnitude, and then reapply The Wiggler.