celanimation

Cel animation, or cel animation, is a traditional animation technique in which artists draw or paint images on transparent sheets called cels. Each cel represents a single frame or a layer of a frame; multiple cels can be stacked over a static background to compose a complete image. The sheets are usually made of cellulose acetate or similar plastic, and are tucked into registration pegs to align with the background and other layers. After painting, the cels are photographed, one frame at a time, using a special animation camera. The resulting images are then projected or transferred to film.

Historically, cel animation dominated mainstream animation from the 1910s through the 1980s and into the 1990s, with studios such as Disney developing multiplane cameras and sophisticated layering. The process is labor-intensive and costly, involving separate drawings for characters and props, cleanup, inking, and painting by hand, followed by careful composition during photography. Color is often added directly to the cels using gouache or acrylic paints, while outlines may be inked.

Typical workflow includes storyboarding, layout, key frames, in-between drawings, cleanup, painting on cels, photographing against painted backgrounds, and compositing. The technique’s major limitations include the slow pace and fragility of physical sheets, plus the need for precise alignment. With the advent of digital ink-and-paint and 3D computer animation, traditional cel animation largely declined in mainstream production, though some studios and artists continue to use it for stylistic reasons, or for archival restoration projects.