American cinematographer (Jan-Dec 1934)

106 American Cincmatographer « July 1934 John Arnold, A.S.C., inspecting the DeBrie "Super' Porvo" Silent Camera. ALMOST seven years ago, the first "Talking Picture" was released. For at least six years, the motion picture industry has been acutely microphone-conscious, striving to suppress every extraneous noise which might interfere with the recording of dialog. From the start, the cinema camera has been one of the chief offenders in this respect, for the intermittent movement which seems inescapably necessary to cinematography, is an inherently noisy mechanism. The first step in overcoming cameranoise was, of course, altering such obviously noisy parts as gears, bearings, etc., and insulating the camera itself by encasing it in a sound-proof housing. These housings — known variously as "Blimps" or "Bungalows" — have progressively diminished in size and increased in sound-absorptive efficiency: but they still interfere to a greater or lesser extent with the free and facile operation of the camera. For at least five years, Cinematographers everywhere have been seeking a really silent camera — one which can be used, uncovered, with any sound system, under any conditions, restoring the full freedom and flexibility enjoyed in the pre-Vitaphone days. For five years, rumors and unverifiable reports have come from engineering laboratories, telling of intensive work , being done in developing such cameras. From time to time, improved cameras hove been shown, or experimental silent cameras tested. Surely the silent camera must be "just around the corner," despite the tight-lipped silence of the engineers and manufacturers. Yet the months have rolled by, and no such camera has appeared. Cinematographers everywhere are asking, "Where is the Silent Camera? When will it be ready for use? What manner of machine will it be?" Properly to understand the answer, we must first appreciate the problem facing the designers. The operation of a motion picture camera is based on the use of an intermittent movement which allows the film to remain motionless during the exposure, then quickly moving onward to reveal the next section of unexposed film. The operation Development of the mechanism for providing this movement is, it seems, unavoidably noisy, while the movement of the film itself gives rise to a certain amount of sound as well. Moreover, the standards of silence are constantly becoming more exacting, as the sensitivity of recording-equipment is increased. A camera which would have been perfectly acceptable five, four, or even two years ago would be objectionably noisy now that "Wide Range" and "High Fidelity" recording is in general use. Since it is recognized that it takes at least two years to engineer and perfect a studiotype camera to the point where it is ready for production, this constant alteration in silence standards is a very grave handicap. At present, the measurement of camera silence is expressed as a rating of "minus decibels": that is, its operational noise is of a volume so many units below the level of average speech. Before the introduction of present highsensitivity recording, a camera with a rating of — 35 db would be considered adequately silent. The best of existing "blimps" ore rated at — 40 to — 45 db, which, with modern recording, is barely adequate. According to studio experts, a silent camera must, to meet today's conditions, show a rating of not less than — 50 db. What is actually available today? Silent camera development has followed two main courses: adaptation of existing equipment, as exemplified in the Fried design; and the creating of absolutely new designs, retoining to some extent the features and appearance of earlier models, as exemplified in the Mitchell and DeBrie designs. The Fried design is essentially a reconstruction of existing cameras — Bell & Howell or Mitchell — in which the silenced camera is placed in a snug soundproofing case, 12x12x12 inches in size. A special focusing system eliminates any lateral shifting for focusing, thereby permitting a much smaller housing. The magazines are not blimped: they ore fitted with beaded moulding, to break up any diaphragm effect, and as they are fitted to the outer cose rather than to the camera, they do not transmit either noise or vibration from the camera. Several of these units ore being used at the Columbia Studio, with excellent results. The first of the new designs to be offered by a major camera manufacturer was the Mitchell. This was first exhibited (in an experimental model) before a meeting of the American Society of Cinematographers in June, 1931, and described in the AMERICAN CINEMATOGRAPHER the following month. A refined model of the camera was used by Hal Rosson, A.S.C., in photographing "Hell Below" last year, and described by him in the AMERICAN CINEMATOGRAPHER in February, 1933. Further refinements have been incorporated in this design, and the camera is now in production and use. It incorporates virtually all of the features of the earlier Mitchell cameras, together with a design which tends to minimize noise. The movement is essentially the same as the famous Mitchell "speed movement," but actuated through eccentrics rather than gears. The film-moving claws move into and out of the perforations much straighter and faster than previously, and leave