Traditional keyframe animation is drawn by hand. This method can be used to create quick and simple animations. Exaggerated poses can be used to show the begging and end of a motion such as punch. This can create a kinetic style but will obviously lack the refinement of full animation.
You can do this by drawing an exaggerated starting pose for the first frame. Draw the next frame as an exaggerated conclusion to the initial pose. For example, if you are animating a man punching someone you can draw the character winding up for a punch on the first frame. For the second frame you should draw the hand extended and the person being punched keeling over due to the blow. When you flip between the two pages, these drawings will create a simple and effective animation.
Keyframes can be used to plan your animation as well. You can use rough keyframe animation sketches to plan interactions between characters as well as to flesh out key scenes. You can use basic frames of character shapes instead of highly detailed drawings. For instance, if you are planning a scene where one character confronts the other, you can plan out each reaction with keyframes. This can help you address issues like the emotional arc of the scene, the intensity of the drama or comedy, and the personality of the characters. This will also give you a preview of the flow and tempo of the animation.
To use keyframes in this manner, you should draw out each animation frame on a single sheet of paper. This will allow you to pass your eye across the page to check the plan for your animation.
One of the main uses of keyframe animation today is to create animation through a process called "tweening." Tweening refers to the frames in between each keyframe. A program like "Maya" will allow you to pose your character, and sets this as a keyframe. The next pose is set as the second keyframe, and the amount of time it takes for the character to move from one post to another is set as well. Several keyframes can be strung together on a digital animation time line, and the computer will calculate the movement necessary for each joint, limb and body part to move to the next keyframe. When you are animating with the keyframes and the tweening method, you can create complex animation quickly.
Difficult animation mus t be broke up into more key frames when you tween. For example, a person getting out of a chair and climbing out of a window would need several key frames. It is a good idea to set a key frame of the person sitting, just getting up and pulling themselves out of the window. The animation should be tested to make sure the computer is tweening the frames correctly in between each action.