We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
Twenty-Lens High-Speed Camera
BY CHARLES W. WYCKOFF
EDGERTON, GERMESHAUSEN, AND GRIER, BOSTON 15, MASSACHUSETTS
Summary— A brief description of the Jenkins camera is presented with illustrations of the optical principles. In co-operation with the Taylor Model Basin, the optical system was redesigned in an attempt to overcome faults encountered with the Jenkins camera. Lenses were mounted on the rim of the lens wheel instead of the flange. This eliminated one fault but introduced others. These faults were all minimized to the extent that the resolving power of the camera is better than that of the film. The 20-lens camera covers a 35-mm sound aperture and holds up to 200 feet of film. It has been operated up to 2350 pictures per second at an //9 effective aperture.
As FAR BACK AS 1910, one of the founders of the Society of Motion Picture Engineers, Charles Francis Jenkins, described a nonintermittent type of motion picture camera which he had invented. It was more than just a motion picture camera, it was in fact, a highspeed motion picture camera capable of recording at a rate of approximately 3000 pictures per second. This astounding speed was truly a great triumph especially since the only film available lacked both strength and quality.
Jenkins achieved these speeds by abolishing the standard practice of intermittent motion of the film and using in its stead continuous travel. To prevent the image from smearing as the film was moved past the picture gate he devised a unique system of image tracking. His tracking system consisted of moving a photographic objective along with the film; essentially, the camera consisted of several cameras operating one after the other. As each camera moved into position, it recorded an image and then moved away allowing the lext camera to commence recording.
To achieve the seemingly complicated action, Jenkins used a lightiight disk or wheel mounted on the shaft of an electric motor, Fig. LA. A series of matched focal-length lenses were mounted near the rim of the wheel with their optical axes parallel to the wheel axis. As the lens wheel was rotated, each lens in turn would sweep past the
* Presented April 6, 1949, at the SMPE Convention in New York.
NOVEMBER, 1949 JOURNAL OF THE SMPE VOLUME 53 469