Kinematograph year book (1950)

488 The Kinematograph Year Bock. vision Committee (en route to which Capt. A. G. D. West, its vicepresident, so tragically met his death) a transmission system was set up by Marconi, and the picture was reproduced on a 16ft. screen by Cinema-Television equipment ( 3 6) . Reports agree that the standard of reproduction was exceedingly high, and the demonstration was enthusiastically received by the technicians present ( 3 7) . The equipment used was practically identical with that which at the end of the previous year had been demonstrated at a Bromley (Kent) kinema (38). On this occasion, a comparison between the B.B.C. transmissions and those from the Cintel studio showed the marked superiority of the latter, a fact which, in conjunction with the different programme needs of the kinema from the private viewer, suggests that if television is to be of full value to the kinema, the industry must be permitted to inaugurate its own transmissions. American Systems In America, RCA, employing the same principle of projecting the image from a cathode-ray tube, have made a number of kinema installations (39). Paramount on the other hand favour the intermediate film system (first experimented upon, of course, by John Logie Baird) ; the image on a small receiver tube is photographed upon film, which is rapidly processed and within 55 seconds is fed to a modified kinematograph projector, where it is projected in the usual fashion (40). While this system has the advantage that an almost normal film is produced, which can be projected with a normal illuminant, and can furthermore be retained for projection to other audiences, it is nevertheless difficult to see how any kinema could meet the heavy running costs entailing a considerable footage of film stock, together with skilled labour. Films are likely to form an increasingly important part of television programmes. A difficulty, additional to those encountered in this country, has had to be overcome in America, due to the fact that a transmission standard of 60 traversals per second has been adopted. As a result, it is not possible to adopt the comparatively simple transmission method possible in this country, which entails merely increasing the film speed to 25 frames per second to match the 50 traversals per second ; instead, in a system developed by RCA, the film is scanned in brief pulses, so that a film running at 24 frames per second can be scanned 60 times per second (A1). The same company has given an apparently convincing demonstration of colour television, which makes use of an exceedingly ingenious principle. A number of years ago, of course, Baird demonstrated a system in which red and green images were produced simultaneously upon opposite sides of a translucent screen. Columbia in America, and Pye in this country, have made use of the sequential system, three-colour filters being rotated in synchronism before the transmitting and receiving tubes. RCA, on the contrary, makes use of a principle analogous to that of the three-colour process block. By an ingenious " sampling " system the three colour components of the image are transmitted in the form of successive pulses, which are reproduced on the screens of three tubes, in the form of points of coloured light, the three images being optically superimposed (42). In the foregoing pages, many new CONTINUOUSLY FOR OVER 25 YEARS ft \ IWi ORGAN'S nave been regularly used by j \ SLIDES LEADING CINEMAS j t MORGAN'S SLIDES LTD., 309, GRAY'S INN ROAD, LONDON, W.C.1 i J Managing Director: HENRY M. MORGAN, M.Inst. P. I. Telephone: Terminus 2536 (2 lines) J