2D Animation Glossary – A What’s This and What’s That Of Animation
Every industry or hobby has its own “language” or every day jargon, that, to beginners or the uninitiated can seem like a whole load of gobbledegook. And 2d animation is no different.
However, don’t be put off by this. It’s really not that hard, and if you have any film, photography or art experience you may have come across a lot of them already since, let’s be honest, 2d animation is really film production through another medium.
Anyway to help you in your quest to become a better 2d animator I’ve made a go-to list or glossary of as many of the key phrases, concepts and principles that I could think of that relate to 2d animation and it’s production. I’ve included a number of “technical” terms that are important in understanding the various features found in the 2d animation software programs that are out there, as well as some timeless concepts that every animator should become familiar with, 2d or 3d.
If you feel there’s anything I’ve missed out, feel free to add a comment at the end and I’ll get it added asap.
Oh yeah, and they’re in alphabetical order for ease of access.
2D Animation Glossary
2-Dimensional, and refers to any image that is created in only two dimensions or axes (X and Y), e.g. a character drawn on a piece of paper like Disney’s Snow White and The Seven Dwarfs.
3-Dimensional, and refers to any image that is created in three dimensions or axes (X, Y and Z), e.g. a character modelled in clay like Nick Park’s Wallace and Gromit.
Similar to the multiplane camera but works in a true 3 dimensional environment. So you can create a camera move in a 3d software package like Maya or 3D Studio Max and export that camera to be used in a 2d animation program – effectively allowing you to combine 3d and 2d elements easily. A 3D camera tool is usually only available in the high-end 2d software packages.
The separation of an animated character or characters into separate layers to speed up workflow and efficiency and save a lot of redrawing. For example, let’s say you have a character that is standing still and eating. Now, you could re-draw the entire character every frame while you are animating the mouth, but a quicker way is to draw once the body and other parts that aren’t moving, and then on a separate layer or piece of paper, do the animation of the mouth. Some of the old Saturday morning cartoons were masterpieces of using layers, even down to moving just the eyes or an eyebrow. Digital animation programs make the use of layers even easier.
A path that can be plotted out and which you set your character or object to follow. An easy way to plan out the screen space your animation will cover.
This refers to a technique which reduces or smoothes the edges of an object if it appears too pixelated (i.e. when you are able to see the square pixels)
Used by an editor to mark out dialogue and audio timing. Bar sheets are rarely used these days since almost everything is digital and the accuracy is far superior and faster.
The “chroma key” techinque of filming live action actors and footage against a blue screen in order to remove the blue and replace it with a different background.
As the name suggests bones are a tool found in various software programs that allow you to create an internal “skeleton” to a character so that you can move limbs and various body parts independently. Sometimes they are also known as “joints”. Mostly used in Flash style cut-out animation they were first developed for 3d animation software to simulate the armatures that are used in stop motion animation.
Where every beginning animator starts, the bouncing ball is the best exercise for learning timing, spacing, volume, character and squash and stretch. Even animators with 20 years experience come back to this exercise. Master this and you’re an animator.
The animation technique where you make a character’s limb “break” – turn it in the wrong direction – usually for 1 or 2 frames in order to accentuate an action and give it more impact. Used more for cartoony style animation.
Short for “celluloid”, a cel is a transparent sheet or piece of film that is used to trace final drawings in traditional animation. The cel is laid over the final drawing, which is then inked or Xeroxed (photocopied), painted and photographed. The transparent nature of the cel means that you can build up multiple layers of characters or objects on separate cels and still see the background. Although the number of layers was often limited since each cel has very slight tint, meaning that many layers results in a slight opacity and change in colour (the painting department would often take this into account and have a tiny variation for a character’s colour depending on whether the layer was at the top or bottom of the stack, in order to keep colour consistency throughout the movie).
Cel use has declined significantly with the rise of digital animation programs which make the process redundant as you can draw directly in the program itself, or scan in your drawings to be inked and painted, with perfect transparency on unlimited numbers of layers.
The special effects technique of compositing two or more images together based on their colour hues or chroma range. Most commonly known as “blue screen” or “green screen”, it involves the removal of the blue or green background (or any other designated colour) and compositing it together with another image.
As the name suggests this is the process of “cleaning up” rough drawings to make the lines cleaner and get them ready to be coloured or painted. Not just a tracing exercise, the clean up artist (or process if done by the animator themself) is also checking the quality of the drawing and making sure it is not “off-model” – in other words the character maintains correct volume, proportion, and design throughout. In digital animation software the clean up process is especially important if you are looking to use the paint and fill functions as the tool will look for solid shapes with closed lines. Any gaps will result in colour seeping into other unwanted areas. Some advanced programs have auto clean up functions when you scan your drawings but their effectiveness is debatable. I’m always wary of anything that says “auto”
See “exposure sheet”
Also known as a graphics tablet or “digitizer”, the modern drawing tablet has begun to take the place of the traditional light box for 2d animation production, as it allows the animator to draw directly into the animation software for a totally paperless production. They come in a variety of sizes, styles and prices, as well as with and without a screen.
An exposure sheet (also known variously as “dope sheet”, “camera instruction sheet”, or “X-sheet”) is a sheet of paper used primarily in traditional animation to mark out the timing of various actions and dialogue. A typical exposure sheet runs vertically from top to bottom and split into a rectangular grid, where each rectangle represents one frame, and every eight frames is marked by a thick line (representing half a foot of film). 3 of these sections equals 1 second of film (8 x 3 = 24 frames). There are usually separate columns for notes, camera instructions, dialogue, and animation layers.
You can download some free exposure sheet templates here
A field chart is basically a grid designed to split the screen space or camera view into small squares or “fields”. Field charts come in 12 fields (12f) or 15 fields (15f) sizes. No longer used as widely in the digital age as before, these were (and still are) invaluable to traditional animators working on paper as they can plot the exact place they want their character to be on screen by using a transparent field chart overlaid on their paper. Most software programs come with field chart functions and will often go further, showing you “action safe” and “title safe” areas.
Field Of View (FOV)
The amount of the observable world or environment that can be seen through the camera at any one moment.
FK (Forward Kinematics)
An animation system where each joint in a chain has to be animated individually and depends wholly on the position of the parent joint.
Flash style / Flash animation
Although this used to mean any animation produced in the program Flash from Adobe, it now refers to any 2d animation that is produced digitally that involves the manipulation of a cut-out style character where keyframes are set and the computer can interpolate the inbetweens. In other words, instead of drawing every frame the animator designs a character with separate moving parts that can be animated independently of the whole.
Flipping drawings is the act of literally flipping through a series of drawings (or frames) to get a rough idea of how they will look when played back properly after being filmed (much like when you made a little flip book as a kid). Flipping can be done with all five fingers of the non-drawing hand while on the light table, or with the thumb as you would when you flick through a book. Old-school traditional animators were said to be able to flip so accurately that they rarely needed to check the accuracy with a camera, since in those days film was very expensive and a pencil test could be very time consuming. However, with digital 2d animation the “art” of flipping is dying off as now all you need to do is press “Play” on the computer and you get an instant accurate flip.
Here’s Disney great Glen Keane flipping a scene from “Aladdin”:
A measurement of the amount of animation or film produced. It comes from the old days where the film negative itself was measured in feet, with 16 frames to each foot. So, 10 feet of film would be 160 frames.
FPS (Frames per second)
This is the rate or speed at which the frames in a sequence are played back. Just to confuse things further, these rates vary depending on country and medium. The universal standard for film is 24 fps (although some experimentation is going on now at 60 fps for HD and 3D movies, most notably “The Hobbit” films from Peter Jackson). Video is 25 fps for PAL (UK and Europe), and 29.97 fps for NTSC (US and Canada).
A frame is a single image of screen time, and multiple frames when played one after the other give the illusion of movement, due to Persistence of Vision (POV). This is how film works, and was really developed in the 19th century by the photographer Eadweard Muybridge. Most film runs at 24 frames per second (FPS).
The “chroma key” techinque of filming live action actors and footage against a green screen in order to remove the green and replace it with a different background.
IK (Inverse Kinematics)
An animation system that allows a chain of multiple joints to be moved by using only one effector or control. An example is a character with an IK leg – you only need to move the foot control and the lower and upper leg joints will move automatically with the knee position being worked out mathematically.
These are the drawings “in between” the key poses. In the old days inbetweens were usually done by the assistant animator or “inbetweener”, and the key poses were drawn the animator or lead animator. People often make the mistake of thinking that inbetweening is an easy job, but it takes a lot of skill and animation knowledge to do it well, since “the magic happens between the frames” as they say. That’s why it’s important to not let the computer do all your inbetweens for you as the computer doesn’t know how to animate, it just does think mathatically – it’s not an artist.
Key poses are the most important drawings or frames in a scene and are therefore done first. They are often the storytelling poses or most interesting or dramatic, but are also very important when doing highly complex or difficult scenes where a character needs to be in a certain position at certain points in time, or when doing lip-sync to get the intonation and points of emphasis. Used in the pose-to-pose animation technique they help the animator to “construct” the scene quickly and show the director an idea in rough form. It also makes it easier to pass on to an inbetweener to fill in the gaps and move the scene forward.
although they seem the same as key poses, keyframes actually refer to any frames or poses that you make in a software program. Since software programs often interpolate the animation between frames, the keyframes are the frames and poses that you actually create and save, and which the computer then interpolates between (tweening). They are often marked on a timeline.
A light table is any kind of desk with a semi transparent pane of glass or plastic and a light source underneath, used mostly in traditional hand drawn animation on paper or cel. The light is there to make tracing through several sheets of paper easier. Most animators’ light tables have an adjustable top which can raised at an angle to make drawing easier. The central disk which is usually made of frosted perspex is rotatable and often has a small hole at top and bottom to make rotation easier. The pegbar is either fitted to the disk manually or comes with it already fixed in place on more expensive models.
These days many 2d animators and artists use lightweight thin light boxes and pads for tracing their drawings. They take up much less space, are cheaper and very portable.
A line test or pencil test is a series of drawings that have been captured via camera, scanner or other input device and then played back in order to get an accurate idea of the timing and look of the animation. As the name suggests they are usually line drawings before being coloured or painted.
Here’s a pencil test of one of my favourite scenes by my all-time favourite animator Bill Tytla:
Lip sync is the process of synchronising your animation to a piece of dialogue – literally synchronising the lips. The traditional process involved using a chinagraph pencil to mark the timing and points of emphasis on an audio track, and then using a bar sheet to mark out those points in frames. The bar sheet information was then transferred to exposure sheets (X-sheets). X-sheets are still used but are now usually in digital format within the software itself, and the audio track is also digitized in a wave format making it much easier and more accurate to synchronise your audio. Some animation programs on the market also even have “auto lip-sync” functions, though the accuracy of them varies.
A mask or matte is shape that is used to cover up certain areas of an image using in live action or real photography. For instance, let’s say you want to have a character walking behind a tree. You simply create a mask or matte object in the shape of the tree and then put it on a layer above the character, so that when he walks it looks like he walks behind the tree.
The multiplane camera is a camera that is mounted on top of a large number of “planes” or layers which allows you to create a realistic sense of depth of field (DOF) in a 2d animation, due to the distance between the layers and cameras. This distance creates parallax which adds to the 3-dimensionality of the final image. It was invented at the Walt Disney company in the 1930s and used to great effect in Snow White and the Seven Dwarfs. Many of the professional level 2d animation software programs these days have a multiplane camera function allowing you to get the same effect without needing a huge warehouse and expensive piece of engineering.
A feature in animation software that allows you to see a certain number of frames before and after your current one, so that you can see the arcs and spacing better. You are usually able to manually set the number of before and after frames as well as the opacity of them. It is sometimes also called “ghosting”. It mimics the way an animator sees drawings on a lightbox.
The difference in the apparent distance or speed between objects. This is why objects far away look as though they are moving slower than those closer to the viewer, even though they may in reality be moving significatly faster. For example, an aeroplane in the sky seen from the ground looks like it is not moving as fast as it is, simply because the distance it needs to cover in order to cross the viewer’s field of view is much greater than say a person who is walking right in from of them.
A particle system is a software that uses algorithms and computer simulations to mimic real world phenomena such as water, smoke, explosions, fire, etc. Many high end 2d animation programs now come with a built-in particle system allowing you to generate these types of effects in your work.
A small strip of plastic or metal with a few pins or pegs sticking out, to which an animator fixes their paper, and helps to keep each frame or drawing in the same position. Many 2d programs come with automatic peg bar detection when scanning to make the line up of the drawings as accurately as possible when they are scanned. A workaround to this is just to stick your pegbar to your scanner and scan your drawings like that.
See “Line test”
Not to be confused with Point Of View, this is the phenomenon where the human eye retains an image for a fraction of a second after it has disappeared, so when we see a sequence of images played one after another at a certain speed we have the illusion of movement. It is said that this is what makes film or any moving image possible.
An animation technique where you draw the key poses of a scene first and then fill in the gaps or inbetweens. This is a more methodical approach to animating where you “construct” the framework of the scene and build it up in layers.
12 Principles (of Animation)
Compiled by Disney animators (most notably Frank Thomas and Ollie Johnston), these are the 12 most important rules or guidelines that make an animation look realistic or appealing. Combining basic physics as well as draughtmanship, art and acting these 12 principles of animation are the bedrock for any good animator. The 12 principles are:
- Squash and Stretch
- Straight Ahead and Pose-to-Pose
- Follow Through and Overlapping Action
- Slow In and Slow Out
- Secondary Action
- Solid Drawing
In contrast to vector animation, a raster system relies on fixed pixel information which means that you can only scale a image down without loss of quality. Scaling an image up creates a blocky low quality image as the pixels become more and more visible.
This is the process of manually tracing over live-action footage to achieve a realistic but artistic look to an animation. A memorable example of rotoscoping is the music video for A-Ha’s “Take On Me” back in 1985. However, it was in heavy use much earlier than that, notably in many of the productions by the Fleischer company in the 1930s and 1940s, and also, in a limited way, in some of the early Disney movies…though there is some debate as to how much rotoscoping was actually done by the Disney animators.
An animation technique that involves the manipulation of physical 3d objects with each frame captured by a physical camera. Also known as clay animation or “claymation”, some notable examples are Wallace and Gromit and Chicken Run by Aardman Studios. An excellent stop motion animation kit for children and beginners is Hue Animation Studio.
An alternative animation technique to pose-to-pose where the animator literally begins at frame 1 and starts animating each frame in chronological order one after the other until they’re finished. Straight ahead animation lends itself very well to creative scenes and bursts of activity, while the pose-to-pose method is more structured. While some animators have a preferred method most will use both or a combination of the two throughout their work. Stop motion animators who come to 2d will often instinctively work straight ahead as stop motion is purely linear (you can only animate straight ahead) so that is what they’re used to. The more experienced you are at animation the easier it is on the whole to do straight ahead animation.
In a software program the timeline is a long bar or strip that shows a sequence’s frame range (start and end frames) and current frame. It can also be set to show your keyframes. Timelines usually run horizontally along the bottom of the screen, but can also be set to run vertically on the left or right.
A made up word, combining “traditional” and “digital”. It refers to the new way of doing traditional drawn animation by combining it or producing it entirely within the computer itself.
A feature in digital animation programs that interpolates between keyframes. See “Inbetweens” for a fuller description.
Vector animation is a system whereby the image information is stored in vectors instead of pixels (raster), which means that it can be scaled up or down without any loss of quality, since the vector values can be recalculated on the fly.
See “exposure sheet”