Traditional animation, sometimes also called cel animation or hand-drawn animation, is the oldest and historically the most popular form of animation. In a traditionally-animated cartoon, each frame is drawn by hand.
The traditional animation process
Traditionally_animated productions, just like other forms of animation, usually begin life as a storyboard, which is a script of sorts written with images as well as words, similar to a giant comic strip). The images allow the animation team to plan the flow of the plot and the composition of the imagery. The storyboard artists will have regular meetings with the director, and may have to re-board a sequence many times before it meets final approval.
Before true animation begins, a soundtrack is recorded, so that the animation may be more precisely synchronized to the soundtrack. Given the slow, methodical manner in which traditional animation is produced, it is almost always easier to synchronize animation to a pre-existing soundtrack than it is to synchronize a soundtrack to pre-existing animation. A typical cartoon soundtrack will feature music, sound effects, and dialogue performed by voice actors. The preliminary scratch track used during animation typically contains just the voices, any songs, and temporary musical score tracks; the final score and sound effects are added in post-production.
Often, an "animatic" (also called a "story reel") is made after the soundtrack is created, but before full animation begins. An animatic typically consists of pictures of the storyboard synchronized with the soundtrack. This allows the animators and directors to work out any script and timing issues that may exist with the current storyboard. The storyboard and soundtrack are amended if necessary, and a new animatic may be created and reviewed with the director until the storyboard is perfected. Editing the film at the animatic stage prevents the animation of scenes that would be edited out of the film; as animation is a very expensive process, there can be very few "deleted scenes" if the film is to be completed under budget.
Design and timing
Once the animatic has been approved, it and the storyboards are sent to the design departments. Character designers prepare model sheets for all important characters and props in the film. These model sheets will show how a character or object looks from a variety of angles with a variety of poses and expressions, so that all artists working on the project can deliver consistent work. Sometimes, small statues known as maquettes may be produced, so that an animator can see what a character looks like in three dimensions. The background stylists are doing similar work for the settings and locations in the project, and the art directors and color stylists will determine the art style and color schemes to be used.
While design is going on, the timing director (who in many cases may be the main director himself) takes the animatic and analyzes exactly what poses, drawings, and lip movements will be needed on what frames. She then prepares an exposure sheet (or X-sheet for short): a table that breaks down the action, dialogue, and sound frame-by-frame as a guide for the animators. If a film is based more strongly in music, a bar sheet may be prepared in addition to or instead of an X-sheet. Bar sheets show the relationship between the on-screen action, the dialogue, and the actual musical notation used in the score.
Layout begins after the designs are completed and approved by the director. The layout process is synonymous with the blocking out of shots by a cinematographer on a live-action film. It is here that the background layout artists determine the camera angles, camera paths, lighting, and shading of the scene. Character layout artists will determine the major poses for the characters in the scene, and will make a drawing to indicate each pose. for short films, character layouts are often the responsibility of the director.
The layout drawings are spliced into the animatic, using the X-sheet as a guide. Once the animatic is made up of all layout drawings, it is called a Leica reel.
Once the Leica reel is finally approved by the director, animation begins.
In the traditional animation process, animators will begin by drawing sequences of animation on paper with pencils, one picture or "frame" at a time. A key animator or lead animator will draw the key drawings ("key" in the sense of "important") in a scene, using the character layouts as a guide. The key animator draws enough of the frames to get across the major points of the action; in a sequence of a character jumping across a gap, the key animator may draw a frame of the character as he is about to leap, two or more frames as the character is flying through the air, and the frame for the character landing on the other side of the gap.
Timing is important for the animators drawing these frames; each frame must match exactly what is going on in the soundtrack at the moment the frame will appear, or else the discrepancy between sound and visual will be distracting to the audience. For example, in high-budget productions, extensive effort is given in making sure a speaking character's mouth matches in shape the sound that character's actor is producing as he or she speaks. (Try making "ah," "ooh" and "ee" sounds out loud, and note how your mouth will subconsciously form a different shape for each sound; good animators must pay attention to such seemingly trivial things).
As they are working on a scene, a key animator will usually prepare a pencil test of the scene. A pencil test is a preliminary version of the final animated scene; the pencil drawings are quickly photographed or scanned and synced with the necessary soundtracks. This allows the animation to be reviewed and improved upon before passing the work on to his assistant animators, who will go add details and some of the missing frames in the scene. The work of the assistant animators is reviewed, pencil-tested, and corrected until the lead animator is ready to meet with the director and have his scene sweatboxed, or reviewed by the director, producer, and other key creative team members. Similar to the storyboarding stage, an animator maybe required to re-do a scene many times before the director will approve it.
In high-budget animated productions, often each major character will have an animator or group of animators solely dedicated to drawing that character. The group will be made up of one supervising animator, a small group of key animators, and a larger group of assistant animators. For scenes where two characters interact, the key animators for both characters will decide which character is "leading" the scene, and that character will be drawn first. The second character will be animated to react to and support the actions of the "leading" character.
Once the key animation is approved, the lead animator forwards the scene on to the clean-up department, made up of the clean-up animators and the inbetweeners. The clean-up animators take the lead and assistant animators' drawings and trace them onto a new sheet of paper, taking care in including all of the details present on the original model sheets, so that it appears that one person animated the entire film. The inbetweeners will draw in whatever frames are still missing in between the other animators' drawings. The resulting drawings are again pencil-tested and sweatboxed until they meet approval.
At each stage during pencil animation, approved artwork is spliced into the Leica reel.
This process is the same for both character animation and special effects animation, which on most high_budget productions are done in separate departments. Effects animators animate anything that moves and is not a character, including props, vehicles, machinery and phenomena such as fire, explosions). Sometimes, instead of drawings, a number of special processes are used to produce special effects in animated films; rain, for example, has been created in Disney films since the late-1930s by filming slow-motion footage of water in front of a black background; the resulting film is superimposed over the animation.
While the animation is being done, the background artists will paint the sets over which the action of each animated sequence will take place. These backgrounds are generally done in gouache or acrylic paint, although some animated productions have used backgrounds done in watercolor, oil paint, or even crayon. Background artists follow very closely the work of the background layout artists and color stylists (which is usually compiled into a workbook for their use), so that the resulting backgrounds are harmonious in tone with the character designs.
Traditional ink-and-paint and camera
Once the clean-ups and inbetween drawings for a sequence are completed, they are prepared for photography, a process known as ink-and-paint. Each drawing is then transferred from paper to a thin, clear sheet of plastic called a "cel," so called because they were once made out of celluloid, but are now made of acetate. The outline of the drawing is inked or Xeroxed onto the cel, and gouache or a similar type of paint is used on the reverse sides of the cels to add colors in the appropriate shades. In many cases, characters will have more than one color scheme assigned to them; the usage of each one depends upon the mood and lighting of each scene. The transparent quality of the cel allows for each character or object in a frame be animated on different cels, as the cel of one character can be seen underneath the cel of another; and the opaque background will be seen beneath all of the cels.
When an entire sequence has been transferred to cels, the photography process begins. Each cel involved in a frame of a sequence is laid on top of each other, with the background at the bottom of the stack. A piece of glass comes down and creates a vacuum, and the composite image is then photographed by a rostrum camera. The cels are removed, and the process repeats for the next frame until each frame in the sequence has been photographed. Each cel will have "registration holes, small holes along the top or bottom edge of the cel which allow the cel to be placed on pegs before the camera, to ensure that each cel aligns with the one before it to prevent a jittery image. Sometimes, frames may need to be photographed more than once, in order to implement superimpositions and other camera effects. Pans are created by either moving the camera, cels, or backgrounds one step at a time over a succession of frames.
As the scenes come out of final photography, they are spliced into the Leica reel, taking the place of the pencil animation. Once every sequence in the production has been photographed, the final film is sent for development and processing, while the final music and sound effects are added ot the soundtrack. Again, editing is generally not done in animation, but if it is required it is done at this time, before the final print of the film is ready for duplication or broadcast.
It should be noted that the actual "traditional" ink-and-paint process is no longer in use by any major animated productions as of present. The current process, termed "digital ink-and-paint," is the same as traditional ink-and-paint until after the animation drawings are completed; instead of being transferred to cels, the animators' drawings are scanned into a computer, where they are colored and processed using one or more of a variety of software packages. The resulting drawings are composited in the computer over their respective backgrounds, which have also been scanned into the computer (if not digitally painted), and the computer outputs the final film by either exporting a digital video file, using a video cassette recorder, or printing to film using a high-resolution output device. The method allows for easier exchange of artwork between departments, studios, and even countries and continents (most American animated productions are actually animated in other countries, primarily Korea, Japan, and India).
The last major feature film to use traditional ink-and-paint was The Swan Princess (1995); the last animated series to do so was Ed, Edd n Eddy. Digital ink_and_paint has been in use at Walt Disney Feature Animation since 1989, where it was used for the final shots in The Little Mermaid. All subsequent Disney animated features were digitally inked-and-painted, using Disney's proprietary CAPS (Computer Animation Production System) technology, developed primarily by one-time partner Pixar. Most other studios use one of a number of other high-end software packages: Toonz, U.S. Animation, and even consumer-level applications such as Macromedia Flash.
The cel & limited animation
The cel is an important innovation to traditional animation, as it allows some parts of each frame to be repeated from frame to frame, thus saving labor.
Take, for example, a sequence in which a girl sets a plate upon a table. The table will stay still for the entire sequence, so it can be drawn as part of the background. The plate can be drawn along with the character as the character places it on the table. However, after the plate is on the table, the plate will no longer move, although the girl will continue to move as she draws her arm away from the plate. In this example, after the girl puts the plate down, the plate can then be drawn on a separate cel from the girl. Further frames will feature new cels of the girl, but the plate does not have to be redrawn as it is not moving; the same cel of the plate can be used in each remaining frame that it is still upon the table.
In very early cartoons made before the use of the cel, such as Gertie the Dinosaur (1914), the entire frame, including the background and all characters and items, were drawn on a single sheet of paper, then photographed. Everything had to be redrawn for each frame, whether that character or item moved in the frame or not. This led to a "jittery" appearance; imagine seeing a sequence of drawings of a mountain, each one slightly different from the one proceeding it. The cel animation process was invented by Earl Hurd and John Bray in television animation, especially that of Hanna-Barbera. The end result does not look very lifelike, but is inexpensive to produce, and therefore allows cartons to be made on small television budgets.
Animation loops are used by virtually all animators. Some movements are repetitive (walking for instance), so a loop or cycle, i.e. an animation sequence which seamlessly repeats, is used. In the case of walking, the character is animated taking two complete steps (right foot to left foot back to right foot to tie-in to the starting position). Then the sequence can be repeated or cycled continuously - or as long as necessary. A loop may also be used in a scene of a car driving, in which the car doesn't "move" on screen but the background tracks or pans behind the car to give the illusion of motion.
In general, loops should be used sparingly and carefully lest they become obvious and distracting. If the driving car goes by the same background scenery more than 2 or 3 times, the loop is revealed and draws the attention of the audience away from the main action.
On the other hand, endless repitition has its own fascination...for an example of creative and entertaining use of cycles/loops, see Ryan Larkin's film "Walking" (National Film Board of Canada - Oscar nominee 1969).
Computers and traditional animation
Though the process described above is the traditional animation process, actual cels are becoming increasingly rare as the computer moves into the animation studio. Often, animators will now draw directly into a computer using a graphics tablet or similar device. Though outline drawings are done in a similar manner as they would be on paper, the computer makes it very fast and simple to paint color into those outlines, thus saving much time and labor in the animation process. The drawings are composited in a computer program on many transparent "layers" much the same way as they are with cels, and made into a sequence of images which may then be transferred onto film or converted to a digital video format.
Though traditional animation is now commonly done with computers, it is important to differentiate computer-assisted traditional animation with 3D computer animation, such as Toy Story and ReBoot. However, often traditional animation and 3D computer animation will be used together, as in Don Bluth's Titan A.E. and Disney's Tarzan and Treasure Planet.
Interestingly the process has now come full-circle, and many modern video games use "cel-shading" animation filters to make their full 3D animation appear as though it were drawn in a traditional cel style. (See "List of cel_shaded video games.") This technique has recently also been used in the animated movie Appleseed (2004), and was integrated with cel animation in the FOX animated series Futurama.
Rotoscoping is a method of traditional animation invented by Max Fleischer in 1915, in which animation is "traced" over actual film footage of actors and scenery. Traditionally, the live action will be printed out frame by frame and registered. Another piece of paper is then placed over the live action printouts and the action is traced frame by frame using a lightbox. The end result still looks hand drawn but the motion will be remarkably lifelike. Waking Life is a full_length, rotoscoped animated movie, as is American Pop by Ralph Bakshi. The music video for A-ha's song "Take On Me" also featured rotoscoped animation. In most cases, rotoscoping is mainly used as a guide to aide the animation of realistically rendered human beings, as in Snow White and the Seven Dwarfs, Sleeping Beauty, Pocahontas, and Anastasia.
Similar to the computer animation and traditional animation hybrids described above, occasionally a production will marry both live-action and animated footage. The live-action parts of these productions are usually filmed first, the actors pretending that they are interacting with the animated characters, props, or scenery; animation will then be added into the footage later to make it appear as if it has always been there. Like rotoscoping, this method is rarely used, but when it is, it can be done to terrific effect, leading the audience to believe there truly is a world where humans and cartoons co-exist. Early examples include the silent Out of the Inkwell (begun in 1919) cartoons by Max Fleischer and Walt Disney's Alice Comedies (begun in 1923). Live-action and animation were later combined to successful effect in features such as The Three Caballeros (1945), Anchors Aweigh (1945), Song of the South (1946), Mary Poppins (1964), Who Framed Roger Rabbit (1988), and Cool World (1992). Other significant live_action hybrids include the music video for Paula Abdul's hit song "Opposites Attract" and numerous television commercials, including those for cereals such as Honey Nut Cheerios, Trix, and Rice Krispies.
- How An Animated Cartoon is Made (http://www.sci.fi/~animato/cartoon/cartoon.html)
- Animation Toolworks' Library (http://www.animationtoolworks.com/library/library.html) - Various essays on the animation process
- Cartoon Network | Animation "How To" (http://www.cartoonnetwork.com/watch/studio/howto/index.html)