Journal of the Society of Motion Picture and Television Engineers (1950-1954)

washing is usually carried out by spray action, and bleaching fluid is applied by jet. The film is vacuum dried. The circulatory pumps are also made of photochemically constant plastic. Washing compartments are provided with electromagnetic devices for synchronizing the movement of the film and the application of the fluid. Sound Recording An important development during 1952 was that of the Magneton sound recording and synchronization system now used in Germany almost exclusively. Klangfilm-Siemens and William Albrecht, both of Berlin, have been especially active in the field of magnetic sound recording and reproducing. Among magnetic sound recorders, Albrecht has a new five-strip tape recorder in which each unit may be used for recording or reproducing. Reverse synchronous operation of all five recording units is possible at normal speed and each tape can be rewound individually at twenty times normal speed. Each unit is equipped with a control switch which automatically stops operation in case of tape breakage or when the tape has run out. Klangfilm-Siemens is also continuing to produce its own well-known Magnetocord instruments, details of which have been previously published. At the beginning of the year, Arnold & Richter brought out a single-tape instrument for either magnetic or photographic sound which can be used for 35mm, 17|mm, or, by changing the spools, for 16mm film.6 Lighting In the field of lighting, Arnold & Richter brought out a new arc lamp using three carbons.7 It is available for 80 to 100-amp and for 160 to 200-amp operation, and is designed for operation with minimum noise. No motor is used to feed the carbons which are so placed (two positive and one negative) as to stabilize the arc. In the field of projection lamps, ZeissIkon has developed the so-called honeycomb condenser which by its structure achieves a high degree of uniformity in the lighting of the picture area and is relatively insensitive to oscillations of the light arc. Descriptions of this system have appeared in International Projectionist.91 During the winter of 1951-52, the firm of Strasser & Deltschaft, BerlinWilmersdorf, brought out a high-intensity 80-amp arc lamp, the "Junior." This lamp has a simple fully automatic single-motor system which has made it popular for studio use. The adjustable motor, which is enclosed, is noiseless and slow-running. By means of an ingenious cylindrical drive mechanism it rotates and feeds the positive carbon at the same time. New carbons for motion-picture lighting systems were put on the market by Ringsdorff-Werke GmbH. It is claimed that these carbons have quieter burning characteristics and provide a closer spectral approximation to daylight. Miscellaneous During the year under review the "Institute for Film and Picture in Science and Education," of Gottingen, published descriptions of some noteworthy experiments made at the Institute with an Askania Z camera and a stereoscopic lens placed in front of the camera lens.9 The double X-ray camera developed by Dr. Metzner and Dr. Bock in Berlin also attracted attention. This equipment includes two cameras coupled together so as to operate alternately. While the film is moving hi one camera exposure takes place in the other. Both film strips thus carry pictures spaced at intervals equal to half the tune consumed in the shift from one frame to the next.10 The firm of Bauer, Stuttgart, produced film reproduction equipment for television film broadcasts made by Fernseh 686 June 1953 Journal of the SMPTE Vol. 60