Verfahren und Vorrichtung zum Erkennen der Lage eines fotografischen Filmes

A length of exposed film has a timing track which extends along one of the longitudinal margins thereof. The timing track includes a begin segment having a first width, an end segment having a different second width and a grating between the segments. The grating consists of alternating light and dark segments having a uniform width different from the widths of the begin and end segments. The two longitudinal margins of the film are scanned by respective sensors as the film advances towards a film processing apparatus. Whenever a segment passes by a sensor, the width of the segment and its position in the timing track are recorded. Since the widths of the begin and end segments differ from the width of the grating segments, the position of the begin or end segment relative to the grating can be established. This information, combined with a knowledge of which sensor detected the timing track, makes it possible to determine the orientation of the film.