Traditional animation

• 1. Introduction

  ›

  Traditional animation is the art of drawing the world into motion, one frame at a time. Before computer graphics changed the industry, virtually every animated film ever made in the 20th century in the United States was produced by hand. Artists sat at desks, pencils in hand, conjuring characters from nothing but paper and imagination.

  The process behind a single animated film is staggering in its complexity. A character might require a dedicated team of artists just to keep its movements consistent across thousands of drawings. Rain, snow, and fire were once filmed separately against black backgrounds and layered in. The plastic sheets known as cels were washed clean after a film finished, the drawings of beloved characters lost forever.

  How did artists manage to synchronize moving images to music before a single frame was drawn? Why did studios choose to record voices first and animate afterward? And what was the last television series in the world to finally abandon the traditional cel? The answers reveal a craft far stranger and more ingenious than the polished films it produced.

• 2. Before a Line Is Drawn

  ›

  A completed animation script is not the starting point for the images on screen. That script first becomes a storyboard, a document resembling a comic book that breaks down each shot by staging, acting, and any camera movement the scene requires. Storyboard artists meet regularly with the director and may redraw a sequence many times before it earns final approval.

  Voice recording comes remarkably early in the process, and the reason is practical. Traditional animation is slow to produce, making it far easier to synchronize drawings to an existing soundtrack than to record actors matching finished animation. The preliminary recording, called a scratch track, typically carries only the dialogue, any songs the characters must perform, and placeholder music. Final score and sound effects arrive later, during post-production.

  Japanese animation and most cartoons made before 1930 followed the opposite path. The soundtrack was recorded after the film was finished, with performers watching the completed footage and matching their voices to the action. Fleischer Studios continued this post-synching practice through most of the 1930s, which is why so many Popeye the Sailor and Betty Boop cartoons contain the muttered ad-libs their animators are known for.

  Once recordings exist, a timing director analyzes exactly which poses, drawings, and lip movements are needed on which frames. The result is an exposure sheet, or X-sheet, a printed table that maps every frame of action and sound simultaneously. For productions driven heavily by music, a bar sheet may replace or supplement it, showing the relationship between on-screen movement, dialogue, and actual musical notation.

• 3. The Cel Itself

  ›

  Earl Hurd and John Bray invented the cel animation process in 1914, and the innovation changed everything about how labor was distributed across a production. Before cels existed, every element of a frame had to be drawn on a single sheet of paper: background, characters, every prop. If a mountain appeared in the scene, the mountain had to be redrawn on every sheet, no matter how slightly it moved or did not move, producing a jittery, flickering result.

  The cel solved this by separating layers. A character could be painted on a thin transparent sheet of celluloid and placed over a background that never changed. The background needed only to be painted once. A table that sat still could remain on its own cel while the person reaching across it was animated on separate sheets. The cel paints were manufactured in shaded versions of each color to compensate for the extra layer of plastic between image and camera; a plate resting on a lower cel would be painted slightly brighter to account for the light lost through that additional thickness.

  The original material, cellulose nitrate, was flammable and was replaced over time with the more stable cellulose acetate. After a film completed its run, cels were frequently washed clean and reused for the next production. In the early days of animation, relatively few were saved. Some studios eventually put a portion of the archive aside to sell in studio stores or present to guests.

  For television and low-budget productions, cels were often cycled, meaning a sequence was photographed once and then repeated several times within an episode. This same bank of archived cels could reappear in future episodes. The labor savings made it possible to produce animation on the tight budgets that television demanded.

• 4. From Pencil Test to Camera

  ›

  Key animators, the artists who draw the principal poses that define a character's performance, work from character layouts as a guide. They draw enough frames to establish the major movements, then pass the scene to assistant animators who add details and fill in missing frames. That process of adding frames between the key poses is called tweening, and the artists who do it are called inbetweeners.

  At each stage, a pencil test keeps the work honest. Early pencil tests were shot on film with animation cameras, which meant animators waited for the developed film to return before they could see what they had drawn. In the late 1970s the industry switched to a video system that stored drawings on analog tape, first reel-to-reel, then U-matic and VHS, making it possible to review tests immediately. By the early 1990s the drawings were stored digitally.

  When pencil animation clears review, it moves to the clean-up department, where artists trace the rougher drawings onto fresh paper, preserving every detail from the model sheets so that the film maintains visual consistency from scene to scene. Approved drawings at each stage are spliced into a working reel called the leica reel.

  For the final photography, each completed cel is stacked in order over the painted background, a piece of glass is pressed down to flatten any irregularities, and the composite image is captured in stop motion by a rostrum camera. Among the most common rostrum cameras was the Oxberry, built from black anodized aluminum, sometimes weighing close to a ton, and requiring hours to set up or dismantle. Cels have registration holes punched along their edges to align each sheet precisely with its neighbors on peg bars in front of the camera; without that alignment, the image at full speed appears jittery.

• 5. Depth and the Multiplane Camera

  ›

  Two-dimensional animation has a fundamental problem: when a camera zooms in on a flat drawing, every element in the picture grows larger at the same rate. In real life, a distant moon does not grow as a viewer walks toward a farmhouse. In a 1957 recording, Walt Disney demonstrated this exact issue and explained how the multiplane camera addressed it.

  The multiplane camera was originally designed by Ub Iwerks, a former Walt Disney Studios animator and director. It is a vertical, top-down camera crane that shoots scenes painted on multiple, individually adjustable glass planes. When the camera moves toward the planes, the nearer planes travel with it while distant elements, like the moon, remain at their original distance. The design by William Garity used for Snow White and the Seven Dwarfs placed artwork on up to seven separate, movable planes.

  Lotte Reiniger and her animation team had constructed one of the first multiplane structures in 1923, a device called a Tricktisch, which was used in filming The Adventures of Prince Achmed. Fleischer Studios took a different approach entirely with their Setback Camera, using miniature three-dimensional models of sets with animated cels positioned at various depths inside them, a method often called the Tabletop Method.

  The spread of multiplane animation helped reduce production times and costs for animated works by solving motion tracking problems that had plagued flat animation. The final Disney film to use the multiplane camera was The Little Mermaid, though by that point Disney's own equipment was not functioning and the work was outsourced.

• 6. Xerography and the APT Process

  ›

  Ub Iwerks applied the electrostatic copying technique called xerography to animation at the Walt Disney studio during the late 1950s. The process allowed animators' drawings to be copied directly onto cels, eliminating much of the laborious hand-inking stage. It saved time and money and made it possible to include far more visual detail in a single frame.

  Xerography was first tested by Disney in a few scenes of Sleeping Beauty, then fully deployed on the short film Goliath II. The first feature film entirely produced with xerography was One Hundred and One Dalmatians in 1961, and the process visibly shaped that film's graphic style. A forerunner of the xerographic method had been patented by Disney animator and engineer Bill Justice in 1944, though it is not confirmed whether that particular technique was ever actually used in animation production.

  The xerographic method left a characteristically sketchy visual quality, which studios addressed over time through refinements including colored toners. In The Rescuers, the characters' outlines were produced in gray rather than black. White and blue toners handled snow and water effects.

  Dave Spencer invented a separate approach called the APT, or Animation Photo Transfer, process for the 1985 Disney film The Black Cauldron. Artists' work was photographed on high-contrast film, and the resulting negative was used to expose a cel coated in light-sensitive dye; chemicals then removed the unexposed portions. Spencer received an Academy Award for Technical Achievement for developing it. The most delicate details still required hand-inking even with APT in use.

• 7. Rotoscoping and the Real World

  ›

  Max Fleischer invented rotoscoping in 1915. The technique involves projecting live-action film footage frame by frame, placing animation paper over the printouts on a lightbox, and tracing the movement of real actors and scenery. The traced result still looks hand-drawn, but the motion carries the weight and physics of actual human movement.

  Full-length rotoscoped films include Waking Life and American Pop. Rotoscoped animation appears in the music videos for A-ha's "Take On Me" and Kanye West's "Heartless". In most cases the technique is used to aid the animation of realistically rendered human figures, as in Snow White and the Seven Dwarfs, Peter Pan, and Sleeping Beauty.

  A related technique adapted rotoscoping for solid inanimate objects. A small physical model was built, painted white with black edges, filmed as needed for the scene, and the printed frames then served as the basis for animators adding detail before the result was xeroxed onto cels. Cruella de Vil's car in One Hundred and One Dalmatians is a noted example. In the 1980s, as computer graphics advanced, 3D digital objects could be generated and printed as outlines for the same purpose, a technique used in Oliver and Company in 1988 and The Little Mermaid in 1989.

  Live-action hybrid productions combine filmed footage with animation added afterward. The tradition extends from Max Fleischer's Out of the Inkwell series, begun in 1919, and Walt Disney's Alice Comedies, begun in 1923, through features including Who Framed Roger Rabbit in 1988 and Space Jam in 1996. The technique has seen persistent use in television commercials, particularly for breakfast cereals marketed to children.

• 8. The Long Goodbye to Cels

  ›

  Hanna-Barbera was the first American animation studio to adopt a computer system for digital ink-and-paint work. Following a commitment to the technology in 1979, computer scientist Marc Levoy led the Hanna-Barbera Animation Laboratory from 1980 to 1983. The system was first tested on two Pac-Man episodes titled "Nighty Nightmares" and "The Pac-Mummy". Starting in 1984 it handled roughly a third of Hanna-Barbera's domestic output, continuing until replaced by third-party software in 1996. Compared to traditional cel painting, the system delivered a cost saving of 5 to 1.

  At Walt Disney Animation Studios, digital ink and paint arrived in 1989, used for the final rainbow shot in The Little Mermaid. The Rescuers Down Under became the first major feature film to use digital ink and paint entirely, relying on Disney's proprietary CAPS technology, developed primarily by Pixar Animation Studios. CAPS restored colored ink-line techniques that had been lost in the xerography era and made it easier to blend shading and integrate 3D CGI elements, as in the ballroom sequence in Beauty and the Beast in 1991.

  Despite this, the transition to fully digital animation was slow across the industry. Many animated television series in the West continued using traditional cels as late as 2004. The last major feature film to use traditional ink and paint was Satoshi Kon's Millennium Actress in 2001. Fox's The Simpsons converted to digital in 2002, King of the Hill followed in 2003, and Cartoon Network's Ed, Edd n Eddy held out until 2004. The television adaptation of Sazae-san remained with cels the longest of any major production, switching to fully digital animation on the 6th of October 2013. The closing sequence of the first episode of Too Many Losing Heroines!, made using cel animation superimposed on live-action footage shot with an 8mm film camera, marked the first new cel animation broadcast on television in ten years and nine months.