Normal picture
The normal image or the “Academy” film image is understood to be the rectangular moving image with an aspect ratio of 4 to 3 (1: 1.333) determined by the Academy of Motion Picture Arts and Sciences in 1929 for normal film , which is based on the format of the cinema camera's picture window is picked out with a mask. The aspect ratio of the camera image window is now 11 to 8 (1: 1.375). In 1932, the required dimensions were 0.631 "x 0.868" (16.0274 by 22.0472 mm). In contrast to the full screen of the silent film, the “Academy” image has moved half an audio track width away from the center of the film.
The small difference between the 4: 3 and 11: 8 aspect ratios (32:24 and 33:24) is due to an uncertainty that existed at the time with regard to the final width of the audio track to be introduced . In particular, one first had to agree on one of the two film edges to which the new dimensions should refer. Because it seemed more important to establish a high level of accuracy for the sound track, the decision was made for the right edge of the film, from which the smaller distance leads to the middle of the sound track. The reason for this was simple: the overwhelming number of cinema projectors were “legal machines”, i. That is, they are operated from the right, and thus the right edge of the film is free for the sound reproduction device to be newly installed.
Until the "Academy" standard and a standard sheet of the American Standards Association were generally recognized, the camera image windows were partially soldered shut in practice. Presumably sound films were produced in this way, which enabled a motion picture that came closer to a square. However, it is doubtful whether the corresponding changes were made to the screens. There was no reason to present the audience with a new, narrower moving picture than it had been used to for 20 years. The titles of this transitional period include Vampyr - The Dream of Allan Gray by Carl Theodor Dreyer and Blackmail by Alfred Hitchcock .
literature
- Report of Standards and Nomenclature Committee. In: Transactions and Journal of the SMPE, Volume XIII, No. 37, May 6-9, 1929, New York, NY, page 29
- ISO 2906, Cinematography - Image area produced by camera aperture on 35 mm motion-picture film - Position and dimensions. 1984