Cels

A cel, plural cels, is a transparent sheet used in traditional hand-drawn animation to hold a portion of the image that will be photographed in sequence with a background. The term is short for celluloid or cell, referring to the sheet’s role as a separate image layer in the animation process.

Materials and construction: Early cels were made from nitrocellulose on which inked outlines and painted color areas were applied. Later, safety materials such as cellulose acetate and polyester became common. Typically a cel is a clear sheet with inked lines on the front and paint on the reverse to preserve line work while providing color. The sheets are cut to fit a specific character or element and are stacked over a painted or printed background.

Production process: In traditional animation, artists first create a developing drawing on paper, which is then traced and inked onto the front of a cel. Color is painted on the reverse, or sometimes applied directly on the cel’s backside. Many cels are prepared for a series of frames; when photographed in sequence with a background, they create the illusion of movement. Lighting and camera setup are calibrated to maintain consistent exposure across frames.

History and usage: Cels were central to the animation industry from the 1910s through the late 20th century, with studios like Disney and Warner Bros. producing thousands of cels for feature films and television. With the rise of digital animation, the use of hand-painted cels declined, though they remain valued for limited-edition releases, preservation, and as collectibles.

Archival and collecting: Original cels are often preserved by studios and museums and can be highly sought after by collectors, with value influenced by condition, rarity, and the sequence they represent.