A virtually transparent magnetic layer is included as an additional layer in a color negative film. Information exchange between various users of the film--such as the camera user, the dealer and photofinisher--is carried via plural longitudinal magnetic tracks on the film, each track being dedicated to the writing and reading of a predetermined set of related parameters. The photofinisher-dedicated track locations fill the exposed image area of each frame. The camera-dedicated tracks lie along the edges of the film between the film perforations, the perforations being widely spaced for this purpose. The film finishing process of the invention responds to data on the dedicated magnetic track on the film to govern the film finishing process.