A film where all scenes no matter what the original colour are represented in shades of grey.
Black and white (B&W) motion picture film generally consists of a minimum of five layers:
- a thin clear gelatin layer without any additions which serves as a protective layer against mechanical damage;
- the light sensitive layer consisting of a suspension of silver salts in gelatin (the actual emulsion). It may have been coated on in one or multiple layers;
- the adhesive substratum which binds the emulsion to the base;
- the base or support consisting chiefly of nitro-cellulose (nitrate film) or acetyl-cellulose (triacetate, safety film);
- there may be a further layer for anti-halation purposes; or a coating of gelatin to prevent curling; or a layer which serves both of these purposes.
FIAF, 1986, Preservation and Restoration of Moving Images and Sound, Federation Internationale des Archives du Film, FIAF, Brussels, Belgium