International projectionist (Jan-Dec 1946)

Record Details:

Something wrong or inaccurate about this page? Let us Know!

Thanks for helping us continually improve the quality of the Lantern search engine for all of our users! We have millions of scanned pages, so user reports are incredibly helpful for us to identify places where we can improve and update the metadata.

Please describe the issue below, and click "Submit" to send your comments to our team! If you'd prefer, you can also send us an email to mhdl@commarts.wisc.edu with your comments.




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.

All-Electronic Tele Shown by RCA Simultaneous Transmission Supplants Sending Each Hue Separately A REVOLUTIONARY advance in television involving the reproduction of colors entirely by electron means, was demonstrated recently by RCA. The new system transmits simultaneously the three basic colors of television — red, blue and green — and focusses them continuously on one screen for the finished picture. Technically, it supplants the twenty-year-old mechanical system of transmitting each color separately — first red, then blue and finally green — with the persistence of human vision blending the separate hues into the composite picture. RCA emphasized, however, that it would be nearly five years before the system could be introduced to the general public, characterizing as "pure bunk" any suggestion that color video was ready for commercial presentation at this time. New Converter Announced A new converter alleviating the problem of set obsolescence also was announced. Attached to present receivers designed to pick up images in blackand-white, it would enable the set owner to continue to enjoy service even though the technical standards of television were changed to accommodate color. The pictures, however, would continue to be in black-and-white, a new set being necessary to receive the color. Announcement of electronic color and the converter came as a major setback to the contentions of Columbia Broadcasting System, which for the last two years has been waging a running battle with RCA on the matter of television's future. CBS had stressed its mechanical system of color video and the pos sibility of black-and-white receivers becoming wholly useless. "Mechanical color compared to electronic color is the horse and buggy compared to the railroad train or, I should say, the Stratoliner," said David Sarnoff, prexy of RCA. Sent by Kinescope Tubes The heart of the electronic color system consists of three kinescope tubes. The tubes receive' separately the signals representing the red, blue and green colors. From the cluster of three tubes, are transmitted continuously as separate units, though all within one channel. Each of the three transmitted images — red, blue, and green — is 525 lines, 30 frames per second, and scanned at the same horizontal rate. This corresponds to the present commercial lower-band standards. The color station would operate in the wave band ranging from 460 to 900 megacycles and each channel would be from 16 to 18 megacycles wide. Under the mechanical system, a disk containing the three basic colors is revolved at high speed by means of a motor. A light behind the disk projects the colors one by one into the transmission circuit. At the receiving end, a COLOR FILM SCANNING UNIT RCA color telefilm camera: A scanning beam of light from a highvoltage (30 kv) cathode-ray picture tube (with glowing screen) is focused through a color slide or film, through special lenses, onto colorselective mirrors, each reflecting a one-color image (red, blue or green) SCANNING CATHODE-RAY TUBE COLOR FILM onto associated p.e. cells for transmission simultaneously, held for complete scanning. COLOR CHANNELS Film must be termed the "Trinoscope," the three color images are projected optically onto the screen where they merge into the composite color picture. On the transmission end, a light beam from a kinescope is focused through a slide of film containing the original color picture. By a system of mirrors and photoelectric cells the colors of the picture are separated into the three components. Then the three components SIMULTANEOUS COLOR PICTURE PROJECTION COLOR CHANNELS CATHODE-RAY PROJECTION TUBES RCA color tele receiver: Signals from the 3-color-band channel are separately received by three 3-inch cathode-ray picture tubes (Trinoscope) and are projected optically as a composite color picture on a mirror and onto a 15" x 20" screen. Black-and-white receivers would tune in green picture signals. second disk and motor are used to put the picture back into the composite whole. As seen on a receiver with a screen 15 x 20 inches, the RCA images were virtually entirely free of flicker and had good brilliance. The best definition came with the slides. The films, which originally had not been scheduled to be shown for another three months, seemed free from separation of the colors when figures moved across the screen, though at times there was a reddish overcast on the images. RCA said that it was hoped to demonstrate "live" studio scenes in electronic color by the middle of next year, outdoor action scenes by the latter part of next year, and large-screen, theatresize pictures in 1948. Video Guys Bragging Already Tele enthusiasts boast that more people saw the recent Army-Navy football game by video sets than saw it at the field, by probably 3 to 1. Since there were 102,000 spectators at the field, this would rate tele an audience of some 300,000. INTERNATIONAL PROJECTIONIST • December 1546 25