PRINCIPLES OF ANIMATION
1. SQUASH AND STRETCH
Humans can squash and stretch a surprising amount, a way to make animations look a lot more realistic is to add this motion. A way to give an example for this is to show a bouncing ball, if you didn't add squash and stretch to the bouncing ball it would look like it has no weight but by adding the squash, you make it look a lot more realistic. Also, people found that if you add a stretch just before the ball hits the ground it looks a lot better, although it isn't realistic, it still looks better.
This is very important to keep your scene flowing, it adds more weight, gravity and flexibility to the object, the viewer notices it a lot more then you might think. There is also the problem with volume in the object, as sometimes the object stretches but doesn't thin out when that happens so it gains volume, that is a big problem in animation and the human mind notices it easily which makes the animation look wrong.
It is also important not to overdo this principle as it can lead to a very unnatural and hard to watch animation. A lot of people try to practice this by using just a 2D square to begin with and squashing while trying to keep it's volume the same, then they would try to do it with a 3d cube and so on.
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2. ANTICIPATION
Anticipation is added to ensure that people who are watching the show know what is happening, it is done a lot in theatre for people that are sat at the back of the theatre. It is basically 'over acting', It makes it easier for the viewer to watch the animation or whatever it is they are watching. A good example is in Charlie Chaplin, as he makes silent films it is even more important for him to add anticipation and he does it very well.
If you were to jump without bending your legs or throw a ball without pulling back your arm it wouldn't look natural at all and the animation would be hard to watch. It is done by guiding the viewers attention to the point that something is going to happen, like this photo with the pocket, the animal is looking at the pocket to alert people to where the pocket is and then reaching high with his elbow to let people know he is about to pull something out of said pocket.
It's important to make it as easy as possible for the viewer to know what is going on without them having to rewind the animation. However, it can also be used to trick the audience by guiding their attention to one spot and then something happening somewhere else.
There is also other steps to anticipation, by adding a pre-anticipation you create an even stronger feeling of knowing what going to happen. when throwing a punch you can pull back to show that they are going to punch but you could take it a step further and wind up that wind up by leaning forward before the pull back in order to show the punch has more power or to 'pre-anticipate' the punch.
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3. STAGING
Staging is making the audience be focused on the thing you want them to be focused on. If the director wanted the audience to see a person looking at his watch, he would make the actor look towards the audience and lift his arm instead of look behind him, this makes the viewer notice this more. It is basically just making one thing in the focus of the frame so the audience notices it most.
The photo below with the people talking shows this very well, the way they are looking directly at each other doesn't help the audience be involved in the conversation, however the second image is a lot better as we can see the characters facial expressions as well as what their hands are doing, this allows the audience to know what is happening a lot more and to focus on their conversation other then something else in the frame.
The main focus of a frame should either be in the centre or in one of the thirds of a camera, this is to draw attention to that thing, there also shouldn't be to many things going on at once, you should let the order of things happening guide the viewers eyes, this helps the person understand everything that is happening.
To take this a step further you should let one action finish before another one starts, this is all down to the timing of the shot, even adding pauses between actions helps to let the viewer know what you want them to look at.
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4. STRAIGHT AHEAD/POSE TO POSE
Straight ahead animation is where you draw each frame as you go, whereas pose to pose animation is where you draw each pivotal moment and then go back and draw the inside frames later .
Pose to pose has better use in animation as it gives you a lot more control, you are able to set down the whole action you want before having to fully animate it, then once you are satisfied with that you can fill in the details. Straight ahead animation is hard to master as drawing one after the other you may not like one of the movement and then have to change a whole bunch of them for it to make sense in the long run, also straight ahead can lead to the character changing size or not ending up where you want it to end.
However, straight ahead animation is great for things that are random and unpredictable like fire, explosions, water etc. Overlapping action is also easier to animate in straight ahead as it is more unpredictable then something like a robot (which would be easier in post to post).
Post to post is broken down into three sections, keys, extremes and breakdowns. You would make the keys first as they set the main animation then make the extremes to see how far the character will go between the keys, and then draw the breakdowns to finish off any unfinished animation, it also makes it look a lot cleaner to add 'imbetweens'. I have heard the term 'pose to pose within pose to pose' which sums it up nicely.
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5. FOLLOW THROUGH AND OVERLAPPING
This is where accessories or hair keep moving around even when the character stops moving himself, this is also called drag. all three of these terms are describing different ways of saying the same thing, it is a way to add a lot more realism to your character. when the body moves the tip of the accessory should be the last to move and then when the body stops it should follow through the furthest. Even extra skin or fat on a character can do the same thing. The amount of follow through and overlap you give something shows the amount of mass that object has, a wet squirrel tail will move less then a dry one.
Animators usually add the extras after animating the body and use the last frame as a reference for where the next one should be because that's where the object would have dragged from.
Overlapping is just a step up from follow through and makes it look more realistic, it also adds more interest to the animation. It is basically just offsetting different body parts in order to make it look more graceful and more real.
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6. SLOW IN AND SLOW OUT
This happens in most things, it is where something accelerates and then slows down as it gets to the end of its action, as an example, if a person was to pick up a remote while sat on the sofa they wouldn't just smack their hand into the remote, they would have to slow down before they touched the remote in order to pick it up. People also accelerate just like a car, so when people start to run, they gain speed and momentum, which adds realism to your animation.
The best way to visualise it is by thinking of a car and how when it accelerates it speeds up and gains momentum, but it then has to slow down in order to stop. The way to animate this is to add more keyframes at the start and end of your animation.
the only thing that moves without this concept is a robot which we all know and with out this motion all of your animations will look very unnatural and mechanical. This principle adds that needed push to make something look real. Almost all movement starts slow, builds speed then ends slow, this is pivotal to making lifelike animations as without it the animation would be hard to watch in general.
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7. ARCS
Arcs (circular motion) are very common in nature, only a few organisms can move without arcs. It is important when animating to give all movement arcs, otherwise all of your work will look very mechanical and robotic. in order to make this look realistic you also have to add slow in and slow out to the movement. Most movements can have an arc added to it, there are subtle moments when an arc can add a lot more character to your animation.
You could even add arcs to movements that are very fast by maybe adding wind lines that are shaped like an arc to add that character. You could even add an arc at the end of a movement as a breath just to add a little extra reality to the animation. Head Animators may make the pose to pose drawings but then tell their assistants to add the inbetweens to the animation to add arcs and just the extra details.
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8. SECONDARY ACTION
This describes small gestures that emphasise the main action in the scene, if a character was shaking his head in disapproval, the secondary action could be him placing his hands on his hips, or even face palming. this adds a lot of personality to your animation and can give an even better example of whats going to happen and what the character is feeling to the viewer. It's also important not to let the secondary action overshadow the original action, an example of this is if the character is sad and he is crying, you wouldn't want to make his hands cover his face to wipe away the tears as it is almost covering the main action.
The principle of staging also comes into play when adding secondary action as you also don't want to let the secondary action go unnoticed by making it be so small, so you would stage the frame that you can see the main action and all the other actions just as well in order for the audience to see it well. You can also add a few secondary actions to add even more personality, for example if your character was sad and the sad face was the primary action, you could add a tear and even animate a hand that comes up to catch the tear before it falls.
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9. TIMING
The personality and nature of an animation is mostly down to the timing of each frame and how many frames there are inbetween each action. If there are a lot of frames very close together then the object is going to move slower but if there is less frames further apart then the object will go faster. If you were to draw one action and changed the amount of frames between it, it could look like it means a different thing, if you have a man the leans his neck from one shoulder to the other, without any frames inbetween it looks like his head is close to coming clean off from a punch but with a lot of frames inbetween it looks like he is dodging that punch.
A movie is generally made in 24fps and if one drawing is drawn on each of those frames that's called drawing on 'ones', if a drawing is drawn every other frame that's called drawing on 'twos' and so on. It's more common to draw on 'twos' because it cuts the work in half and also it makes slow actions look smoother.
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10. EXAGGERATION
This is a typical thing in animation, most actions can be taken to the next level to increase the effect it has on the viewer. Walt Disney was the first to push this in his animations, he would tell his animators to make the frame look more real but when they made the physics and drawings look more real he would hand it back and say that's not what he meant. Disney wanted the animators to make the idea and essence of the action more easily to read and look more real.
So if a character was exited, make him more exited and if a character was sad make him more sad. When motions are quick, they need to be even more exaggerated in order to make it more obvious on what just happened. A good rule to follow is to push the exaggeration to it's limits, and then to wind it back until it seems satisfactory. It's important not to overdo exaggeration however as it can make the animation look fake and hard to watch, unless you were going for that effect.
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11. SOLID DRAWING
This is the skill of making a character feel like they are in a 3D space by adding volume, weight and balance. A strong use in animation is being able to draw a character from every angle, this is one of the skills Disney wanted in the 20's when hiring people, he thought that he could teach people animation easily but he couldn't teach them how to draw, so if you could draw, you were in. When doing a rough drawing of a character you should use cubes, cylinders and spheres, this is to make it easier to create the 3D space that it is in. Overlapping lines is also a very good way to add '3Dness', without it it doesn't look good at all, it's a little detail that has a big effect.
Avoiding symmetry is also very important to make a character look 3D. In 3D animation it is also important to avoid a thing called 'twinning', this is where the arms and legs are doing the same thing, this makes the character look weightless, if you make the character lean to one side it adds like he has to keep his balance in the 3D environment.
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12. APPEAL
This is the fact that characters that you design should be at least a little bit pleasing to the eye, they should have some aspect that is likeable about them, it applies to every character, not just the hero, it doesn't have to mean good looking, it can also mean interesting and like you want to learn more about them. Giving your character a dynamic design has a strong factor in making a character appealing, using a variety of shapes and sizes helps a lot to make a character appealing, there is no limit to what kind of shape a character can be. finding the aspect of a character that makes that character who they are and making it more obvious is a great way to boost appeal. If you keep your character simple and easier to look at the viewer will want to watch more of that character. having no parallel lines is also a good way to make the character more appealing as in nature there are only a few examples of parallel lines, so not having them gives the character a lot of personality.
It is a fairly simple principle but it has a lot of different ways to achieve it, if it is done properly your character will be very appealing and people will want more, I think a good example of an appealing character is Squidward, he is lanky and has a massive forehead and nose which gives him a lot more personality then if he had a normal sized nose and had normal proportions.
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