Drawn-on-film animation, also known as direct animation or animation without camera, is an animation technique where footage is produced by creating the images directly on film stock, as opposed to any other form of animation where the images or objects are photographed frame by frame with an animation camera.
Norman McLaren drawing on film
A portable box used by Steven Woloshen to scratch the film stock
Film stock is an analog medium that is used for recording motion pictures or animation. It is recorded on by a movie camera, developed,
edited, and projected onto a screen using a movie projector. It is a strip or sheet of transparent plastic film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of the crystals determine the sensitivity, contrast and resolution of the film. The emulsion will gradually darken if left exposed to light, but the process is too slow and incomplete to be of any practical use. Instead, a very short exposure to the image formed by a camera lens is used to produce only a very slight chemical change, proportional to the amount of light absorbed by each crystal. This creates an invisible latent image in the emulsion, which can be chemically developed into a visible photograph. In addition to visible light, all films are sensitive to X-rays and high-energy particles. Most are at least slightly sensitive to invisible ultraviolet (UV) light. Some special-purpose films are sensitive into the infrared (IR) region of the spectrum.
A film strip
A short strip of undeveloped 35 mm color negative film