70 mm film

70 mm film (or 65 mm film) is a high-resolution motion picture film format. As used in camera, the film is 65 mm wide; for projection 2.5 mm are added along each outer side of the perforations for magnetic strips holding six tracks of surround sound, although in truth, the magnetic sound system is rarely used anymore. Each frame is five perforations tall, with an aspect ratio of 2.20.

With the introduction of "Todd-AO", 65 mm/70 mm became popular during the 1950s for the wide screen, sharp picture and, most importantly, high quality sound. The advent of low-grain film stocks and availability of digital soundtrack systems for less expensive and more widely projectable 35 mm film led to a decline in use of this expensive format in the 1990s. Lawrence of Arabia is a well-known film in 70 mm format; the clarity of its picture is apparent in theaters, though much less so on VHS or DVD.

There is a subset of 70 mm film known as Showscan, in which the picture is captured and shown at 60 frames per second, which can have beneficial effects on qualities like image strobe, flicker, and grain. It never caught on with mainstream cinema, and is primarily used for theme park simulation rides.

A horizontal variant of 65 mm/70 mm, with an even bigger picture area, is used for the high-performance IMAX and Omnimax formats. The Dynavision and Astrovision systems each use slightly less film per frame and vertical pulldown to save print costs while being able to project onto an IMAX screen. Both are rare, Astrovision more or less exclusively occupying Japanese planetariums.

Steven Spielberg's Close Encounters of the Third Kind was mainly shot on 35 mm film, but the effects sequences were shot on 70 mm film. Special effects man Douglas Trumbull (who later invented Showscan) decided to do this so that there would be no loss of quality that might subconsciously "warn" moviegoers of an impending effects sequence.

Starting in the late 1950s and continuing until the mid-1990s, many 35 mm films were converted onto 70 mm prints for premiere showings in large cities or venues which could accompany the format. Often this was not just for issues of image size, but more because of the six magnetic sound tracks available (versus two optical sound tracks on 35 mm) with 70 mm prints. Since the introduction of DTS, SDDS, and Dolby Digital, 70 mm lost this advantage, and a significantly lower number of 70 mm prints are struck today.

The last major studio feature film to have been shot entirely on 65 mm is Kenneth Branagh's Hamlet . Since then, the format has been occasionally used for visual effects shots. Recently, big waves in the 70 mm enthusiast crowd were made upon rumors that Terrence Malick would shoot The New World (2005) entirely on 65 mm; this was determined to be too expensive for the entire shoot, however, although certain portions were indeed shot in 65 mm.

Technical Specs

Standard 65 mm (5/70) (Todd-AO, Super Panavision)

Showscan Same as Standard 65 mm except

IMAX (15/70)

Omnimax Same as IMAX except

Dynavision (8/70)

Astrovision (10/70)

Famous 65 mm/70 mm films

Related articles

See also: 70 mm film, 1950s, 1990s, 2005, 35 mm film, Akira (film), Around the World in Eighty Days (1956 movie), Aspect ratio (image), Baraka (film)