The Movietone process is for the 1927 cinema the first photographic sound recording device on film, along photograms . It was used by the Fox Film Corporation which bought the patents in July 1926. The first film using this method 1 , The Dawn ( Sunrise ), shot in the United States by the German director Friedrich Wilhelm Murnau , was released in 1927 2 .
All the first attempts, successful or almost, synchronization of the sound with the image, were on the principle of coupling of the sound reader on cylinder or on phonographic disc, with the camera for the shooting , and by the next, with the projection apparatus . As early as 1895 , Thomas Edison , inventor of the Phonograph and with his assistant the electrician William Kennedy Laurie Dicksoninventor of the first film camera, the Kinetic , stubbornly researches the realization of this couple with a single essay, Dickson Experimental Sound Film and the launch Aborted Kinetophone, sound version of the Kinetoscope , a viewing device for films shot with a kinetograph.
According to the same principle, the Chronophone developed by Georges Demenÿ , bought by Leon Gaumont , allows recording from 1902 the image and voice (actually in play-back ) of singers and whimsical music hall . These are the phonoscenes , whose first film director, Alice Guy , is the instigator. The phonoscène, later reproduced identically on optical sound film, are now a precious memory of the song at the beginning of the xx th century. There are some 140 phonoscenes.
Other processes are created in the first twenty years of the xx th century, but the only one that gives satisfaction is the Vitaphone , marketed in 1924. Burner drives and camera are each equipped with a synchronous electric motor that rotate at the same constant speed, thus ensuring synchronism of image and sound. Same couple at the screening. Don Juan in 1926, then the famous Jazz Singer in 1927, opened the era of sound cinema with the Vitaphone.
Although reliable in general, the process is however subject to a few failures of synchronism. But above all, it can not cope with possible accidental cuts of the film 35 mm . We can repair the damaged film by removing the damaged images and gluing, but the sound can not be modified, it is then longer than the image, therefore out of sync. To remedy this, it is necessary to draw a new copy and to recycle the damaged copy, obvious financial loss.
The Movietone process largely avoids this artistic and financial problem. The sound is recorded as the image on the photo-sensitive surface of the film. “The Movietone sound is said variable density , the recorder has a magnet with two branches between which a tensioned wire is traversed by the modulated electric current from a microphone. The wire diverts according to the intensity of the current and masks more or less a strong light which crosses the two branches. The variations of this light, collected by a lens, impress on the side a film film 35mm. This one, after development, is copied on the film between the images and one of the rows of perforations 3 . “In order to avoid the zone of jerky turbulence due to the intermittent scrolling of the film in front of the window of the projection corridor, the sound is shifted in the copies to be read in a continuous scrolling zone after stabilization, in order to avoid any sound deformation . This offset is 20 frames after the window. The sound corresponding to a photogram is thus present 20 images, ie 38 centimeters further. It is easily understood that if the film is amputated at a location X, it is the sound of the second preceding ( 20 images , that is to say, the 24 images of a second projection) that will be missed at the reception by the public. . But after this lack of sound, synchronism image and sound resumes perfectly.
The sound Movietone however has the defect of aging badly. The scratches due to the friction of the film in the projection corridor, the oil, the adhering dust, attenuate the audible dynamism of the optical track, the sound becomes pasty and in the long term poorly audible. It is replaced in 1929 by the Photophone which has the advantage of not deteriorating and allowing the recording of two tracks side by side. “Radio Corporation of America (RCA) launches one year later the Photophone sound that is said to fixed density, the recorder is equipped with a mirror galvanometer which oscillates according to the variations of the intensity of the current out of the microphone. The mirror is illuminated by a strong light that is more or less returned to a lens that records the amplitude of the received illumination on 35 mm film. This process has the advantage of not deteriorating 4 . ”
Notes and references
- ↑ ( in ) ” Movietone’s Synchronized Shorts and Features ” [ archive ] (accessed 22 January 2014 )
- ↑ http://foxmovietonenews.com/ [ archive ]
- ↑ Marie-France Briselance and Jean-Claude Morin , film grammar , Paris, New World ,, 588 p. ( ISBN 978-2-84736-458-3 ) , p. 163
- ↑ Idem