Magnetic film

 AudioVideo recording tape manufactured using a base of the same physical film stocks, e.g., 16mm, 35mm, etc., and which contains a magnetic area running longitudinally down the film for the recording of an audio track or tracks. Magnetic film is 3-5 mils thick, so that the same length of film and magnetic film will be of equal diameters when wound on reels. Full-coat magnetic film has magnetic oxide applied across its entire width. Striped magnetic film can have one or more thin stripes of oxide applied longitudinally on the film base. There is usually one (wide) stripe containing a single track of audio (in the same size and location as track-one of a 3-track), while another (smaller) stripe is placed on the opposite side to make the film pack evenly when wound together, usually known as a balance stripe. The balance stripe is sometimes used to record timecode from 1/4 inch or DAT timecoded production masters. Also called mag. Not used since the advent of synchronized audio multitrack recording. See film soundtrack.