12x is a very standard unit of time in cartoons. It's roughly the time it takes for a human to take a step in a normal walk. A fast walk would be 8x per step. Pepe Le Pew's hop cycle is 12x per hop.
Here is a perfect scene to learn the essential concept of animating to tempos. The scene is very simple and basically just moves from one pose to the next to the beat. No fancy overlapping action or secondary motions to distract you from the core concept of beats.
It's good to study just because it is so simple. A beginning animator needs to get used to how long a beat is in frames. This song is a 12x beat. Sing along and tap your foot to it, until you memorize the rhythm. Then do it later when you don't have the animation in front of you. After a while you will know what a 12x beat feels like.
THE FIRST FEW "KEYS"
The music in this scene is 2 beats per second, or 12 frames per beat.
Each of these frames below is a key drawing. They are the drawings that you see and feel for each beat - the important drawings. The rest of the drawings are on the way to these keys. Those are the inbetweens.
Each key is either 12x or 24x away from the other keys next to them.
You should number the keys according to which frame they would appear in your animation test. Number your ex sheets that way too.This would be frame 25 (1 frame past the first 2 beats of pose 1.)
THIS IS THE SECOND POSE IN THE SONGEach of these frames below is a key drawing. They are the drawings that you see and feel for each beat - the important drawings. The rest of the drawings are on the way to these keys. Those are the inbetweens.
Each key is either 12x or 24x away from the other keys next to them.
You should number the keys according to which frame they would appear in your animation test. Number your ex sheets that way too.This would be frame 25 (1 frame past the first 2 beats of pose 1.)
Add 24x to to frame 25 and you get frame 49. Got it?
Then it goes to a new pose on every beat. Watch the film frame by frame. Number the inbetweens by counting backwards from the key. If there are 4 inbetweens on the way to frame 49 and they are on "1's", then they will be numbered 48, 47, 46, 45
The mouths are animated on separate levels, so that the body and head animation can be cycled or reused. When you animate this scene, animate the actions first. After you shoot it and see it working, then go back and animate the mouths on a separate level.
Some of the poses are held for a few frames once they stop. The face keeps singing while the body is stopped.
Watch the clip. The song starts on the second scene. If you copy this animation, you will benefit greatly. If you shoot it, send me a link and I will post some of them.
CLICK HERE TO SEE THIS LUCKY RABBIT DANCE!
Just to confuse things, the clip is running at 30x per second ... like video. Film is 24x per second so you have to calculate a bit. Some of the frames are repeated to make it run at 30x per second.
That's why you see some double images in the clip. If you follow my instructions above as to how to number the drawings, it will end up at 24x per second.