Without squash & stretch there would be no sense of weight, mass or velocity in animated objects thus making animations look unrealistic
in this example you can see the differences "A" doesn't use squash & stretch making it unrealistic because when a ball bounces it compress and expands shown in "B"
Anticipation
Using anticipation helps the audience prepare for actions sequence making the animations seems more realistic. This technique can also be used for less physical actions like a character looking off-screen anticipating someones arrival.
in this example the bending of the knees before the jumps is the anticipation.
Staging
Is the presentation of an idea so thats its clear. the idea can be action, a personality or mood. the key idea is made clear to the viewer . An important objective is to lead the viewers eye to where the action will occur so they don't miss anything. A good example is motion, since the eye is drawn to motion in an otherwise still scene. In a scene where everything is moving the eyes will then be drawn to the still object.
Straight Ahead Action and Pose to Pose Action
Straight ahead in hand drawn animation is when the animator starts at the first drawing in a scene and then draws all of the subsequent frames until it reaches the end of scene.
example of straight ahead action
Pose to pose action is when the animator carefully plans out the animation,draws a sequence of poses. i.e the initial some in between and the final poses and the draws all the in between frames. This is used when the scene requires more thought and poses and timing are important.
Follow Through and Overlapping Action
This is a example of follow through its when the javelin has been thrown but the man continues his throwing motion ( he follows through to the end)
Overlapping is when the start of the second action is shown before the first has finished
Slow in and Slow out
Slow in means slowing down the speed of an action when reaching a main pose.
slow out means accelerating again upon leaving a main pose. So with both movement should be. Slower in frames to an extreme right before reaching it and right out leaving it. Faster between two consecutive extremes.
an example of slow in and out
Arcs
Most natural action tends to follow an arched trajectory, and and animation should adhere to this principle by following implied arcs for greater realism. This can apply to limbs moving by rotating joints or thrown objects.
example of arc (moving arm)
Secondary Action
Is an action that results directly from another action. It can be used to magnify the interest in a scene by adding complexity. It should always be used inferior to the primary action in the scene to not take away it's focus. An example might be facial expressions on a character as secondary action and the body would be expressing the primary action.
Timing
Timing is when the number of drawings or frames for a given action translates to the speed of the action shown. If too much time is spent then the viewer may lose interest if too little time is used the viewer may not understand or notice the action.
Exaggeration
Exaggeration is distorting the action to enhance objects if only one thing is exaggerated then the it may stand out too much or if too much is exaggerated then the entire scene could look unrealistic.
this is an unrealistic exaggeration being used well in this cartoon making the scene look interesting
Solid Drawing
Solid drawing is being able to draw the characters from every angle in a believable manner so they look alive. Being to add anatomy, weight balance, light and shadow to the characters is a vital skill the animator needs.
Appeal
Appeal in a cartoon character corresponds to what would be called charisma in an actor.A character who is a appealing is not necessarily sympathetic villains or monster can also be appealing to viewers making the characters real and interesting to the viewer is important.
