Which principle is NOT considered one of the 12 key animation principles?

The principle that is not part of the 12 key animation principles is zoom animation. The 12 principles of animation, developed by Disney animators Ollie Johnston and Frank Thomas, serve as fundamental guidelines to create lifelike and engaging animations. These principles include concepts like anticipation, which prepares the audience for an action; staging, which directs the viewer's attention to a particular action or emotion; and squash and stretch, which gives the illusion of weight and volume to animated objects.

Zoom animation, however, does not fall within these foundational principles. While varying camera angles and zoom effects can enhance storytelling in animated films, they are techniques related to cinematography rather than principles specific to character animation and movement. Understanding the distinction between these principles and techniques is important for animators to create more dynamic and appealing animations.