Responsibility of the director
The director is responsible for decisions regarding the overall pacing and planning of the whole story or a particular sequence of it.
This can involve sequences of several minutes' duration or of only a few seconds. He must also decide how these sequences should be organised into scenes.
How long should each scene be? What should be the pace of the action in the scene? What should be the pace of the action in order to hold the interest of the audience? How can ideas in the story best be put over to the audience? These are the problems the director must solve. Going down to yet shorter periods of time, to individual actions, the responsibility is shared between the director and the animator. But the director still has overall control.
The animator should, however, add some ideas of his own as to how certain effects can be achieved—just as an actor would in live action. The smallest units—individual drawings and frames—are almost entirely the animator's province, and this is where his particular skill lies. How does a ball bounce? How does a character react in surprise, or snap his fingers? These are problems the animator must solve by his feeling for and knowledge of the subject.
An animated film usually takes a long time to produce. During this period it is essential that the director should keep a constant check on how the production is progressing and how closely the original timing and concept have been followed.
Most animated films are made to a predetermined length. A TV commercial must be an exact number of frames and a longer film will probably have to fit between fairly narrow limits. One of the director's problems is to fit the action to the time available.
First divide the story into sections or sequences of convenient lengths. Run through each section mentally as many times as necessary to absorb all the important story points. Then run through each section again, timing it mentally with a stop watch. Add up all the timings to give an overall total. This is sure to be more or less wide of the mark. If it is fairly close, see whether a sequence can be adjusted to bring the total about right. If it is much too short, more business must be invented to fill the time available. If it is much too long, maybe a whole sequence must be omitted.