Secondary Action - Research

In every animation scene there is a primary action, intended to get a certain point across. For example, the primary action in a walk-cycle is the character walking. Sometimes however, more emphasis is put on the primary action using one or more secondary actions that result directly from the primary action. In a walk cycle for example, a secondary action could be the character swinging his arms or expressing an emotion using facial expressions. Use of secondary action in a scene often gives more life and dimension to a movement or character.

Example of a Secondary Action - the primary action is the swinging of the pendulum, the secondary action is the movement of the "tail":



An important rule about secondary action is that it should not dominate or detract attention away from the primary action. If this is the case, the secondary action is most likely wrong for that particular scene, or staged incorrectly.

There are dangers involved with using facial expression as a secondary action, in that these subtle expressions may not be noticed by the viewer when combined with a dramatic movement. It is often considered better to include facial movement at the beginning or end of a greater movement, rather than during. In some scenes the facial expression may be the primary action, in which case the secondary actions must be carefully planned around it so they do not detract from it. In other scenes, the facial expression may be used as a secondary action, in which case it should be staged so that it's obvious and visible to the viewer, yet isn't dominating the primary action.

Example of facial expressions as primary action with carefully placed secondary actions that don't detract from the focal point:



A reccommended way of making sure any secondary actions remain subordinate to the primary actions is:

• Go through and animate the primary action, make sure that it looks
  the way you want it.
• Then go through the scene a second time and animate the secondary
  action, making sure that it all works the way you want it to. And that it
  doesn’t overwhelm or detract from the primary action in any way.
• Then go through a third time to make sure that the rest of the
  animation relates to the primary and secondary actions the way they should.

(Quoted from an article found at http://www.animationbrain.com/secondary-action-2d-animation-principle.html)

References:
De Stefano, Ralph A. "Secondary Action". [Online] Electronic Visualization Laboratory, University of Illinois at Chicago. http://www.evl.uic.edu/ralph/508S99/secondar.html. (accessed 17 Nov 2010)

"Flash Animation Tutorials - Secondary Actions" [Online] http://www.youtube.com/watch?v=2yUSOBD4igc (accessed Nov 17 2010)