Motion Picture News (Sept-Oct 1921)

2330 Motion Picture News Los Angeles Producer Places Excellent New Camera on the Market Pronounced a Triumph of Moving Picture Camera Fabrication Los Angeles is not only the motion picture producing capital of the world, but when all the new cameras and photographic devices now in process of perfection shall have been placed upon the market, she will almost surely be recognized as the great American center of photographic engineering. The first perfected motion picture camera to be offered to the public by a Los Angeles producer is the Mitchell, manufactured by the Mitchell Camera Company. This camera, together with its tripod, has been developed by George A. Mitchell and his associates and is pronounced by experts to be a triumph of high class camera fabrication. The Mitchell Camera is in two parts, the camera box and the base. The box is cast of aluminum; alloy in one piece, accurately machined, and ^11 the working mechanisms are assembled in this case. The base is made of the same material, also cast in one piece, accurately machined. The Iris, four way mattes, matte disc, turret, plate and turret are mounted on this frame. Dove-tailed guides or tracks are mounted on this base, on which the box slides. This is actuated from the rear by a handle operating pinions, meshing with racks ; a release button in the center of the handle operates the locking mechanism so that in either position the camera is securely locked, and may be instantly shifted from the photographic to the focusing position and vice versa with one hand. Focusing is accomplished by shifting the camera to one side. The focusing tube on the James Van Trees. Paramount cameraman, zLnth his new Mitchell camera, the fourth of the kind made. The Mitchell is manufactured in Los Angeles door carries a series of magnifiers, and you view the magnified image on a ground glass; when ready to take the picture, turning the handle brings the photographic aperture back in front of the lens. In its photographic position, the position of the lens has not been changed, an advantage that is obvious to all cameramen. In this position the focusing tube is now behind another lens and becomes the finder. This operation is practically instantaneous and requires no other motion than turning the handle. Immediately in front of the shutter, but in the base, is a matte disc which carries all the " stock " mattes, together with a special slide where any special shaped matte may be inserted; this is operated from the outside. An index pin is provided which locks the disc in the proper position. All these mattes are readily accessible and are at the instant service of the operator. With these mattes any rectangle opening may be had. Either matte may be operated independently of the other and either matte will cover the whole aperture; they are inside protected from dust and protected from the light, so there is no dangef of reflections from electric lights. / The Iris is pivotally mounted and is adjustable to any part of the aperture. There are thumb-nuts by which the Iris may be moved up and down and to either side. lu the lower comer of the turret plate is the rising and falling front; by pressing in on a knob a pinion is disengaged from a stop and engages a rack; turning the knob causes the turret to revqlve slightly, giving the equivalent of 15 degrees tilt of the tripod, but without the accompanying distortion. The front is graduated so the lens may be brought to center in an instant and releasing the pressure on the knob locks the; turret. The turret is revolved independently of this mechanism. A slide is provided on the focusing tube, which may be opened, giving access to the ground glass; a matte slide is placed immediately in front of the ground glass and one behind the glass, the object being to slide pieces of ground celluloid in this rear slide and, while the camera IS in the focusing position, mark out an object that is to be matched up in a double exposure, which is used to line up the second setting. This IS for quick and more or less rough work. The most accurate way is to use the punch we provide, placing a piece of negative over pilot pins and punching out a frame of picture. This may may be inserted in the slide immediately in front of the ground glass and the second exposure viewed through this negative. This negative may also be used as matte by cutting out the parts of the scene to be double exposed, painting the remainder black and then slipping this in the matte disc and revolving to the aperture. If it IS not desirable to use the film for a matte, any thm opaque material may be used. In this method of matting you are always focusing through the actual matte the picture is to be photographed through, so the possibility of error IS reduced to the minimjum. The movement of the camera is made of the best grade of tool steel, hardened and ground all over and lapped with a diamond lappe to a mirror finish and very close fit. There are three cams which operate this mechanism; a three cornered cam moves the pins up and down • a second cam of the same design, but smaller, operates the pins in and out; while a third face cam relieves the tension and applies it again to the film. Through a cycle of operation the film IS held in contact with the aperture by the face cam; the pins enter the film, the pressure is released and the film is brought to the new position; the pressure is again applied and the pins withdraw. The film is at all times positively held and placed in position, yet during the move(Continued on page 2336) I