Normal film

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Normal film is the traditional name for the most widespread format of motion picture film , photographic film for cinema and advertising film productions, with a width of 34.975 ± 0.025 millimeters, also known as 35 mm film . The original dimension was 1⅜ inch (34.925 mm). William KL Dickson stood at the origin of this strip width .

In 1913 , Oskar Barnack also used 35 mm film for the first time in 35 mm photography (original Leica camera ).

The ISO 491 standard defines the dimensions of the normal film. The standards handbook 17 of the International Organization for Standardization , based in Geneva, is a collection of the technical regulations relevant to cinematography .

Normal on normal film are the film width, arrangement and shape of the perforation holes , position and size of the individual image to be exposed (camera regulation), position and width of any optical soundtrack and the details of the playback film (copying regulation).

To date, there is no international standard for the frame rate, either for recording or playback. 24 frames per second is normal from national practice in the United States of America. In one minute, 27.36 meters of film run through a normal film camera. The relevant standards were agreed in 1929 at the Academy of Motion Picture Arts and Sciences , Los Angeles. Today the American National Standards Institute , New York City, is responsible.

In a broader sense, there are also the following norms about normal film: 1000 frames per minute is a historical number that occurs differently as a frame rate. The original film step , as defined by Dickson, is one sixteenth of the Anglo-Saxon foot. Normally you turn the crank of a classic film camera twice a second, because a winding sprocket with eight film steps sits on the crank axis. The normal film step is linked to the normal picture in the aspect ratio three to four. Normal raw film portions are 100, 200, 400, 500, and 1000 feet. From 1936 onwards, the normal demonstration act of 2000 feet was adopted in order to reduce the mutilation of copies.

Relevant ISO regulations

  • ISO 491, raw film; the four perforation types negative (originally " B ell & H owell"), positive ( " K odak S tandard"), DH ( D ubray- H owell) and AC ( A merican C inemaScope)
  • ISO 543, security film
  • ISO 23, used in camera
  • ISO 70, sound track
  • ISO 2906, image window
  • ISO 2907, projectable image section
  • ISO 2939, demonstration positive
  • ISO 3047, "H" (undred foot) camera coil, hundred feet capacity
  • ISO 4241, start and end belt

supporting documents

The term normal film appears in all German-language specialist literature. These are representative here

  • Cinema paperback from Philips , 1955 (p. 56);
  • Kinotechnisches Taschenbuch by the company Eugen Bauer, 1955 (p. 1);
  • Technical paperback from Zeiss-Ikon , 1956 (p. 18)