What Makes the Kinemacolour Colour?

Kaipara and Waitemata Echo, 20 November 1914, Page 4

What Makes the Kinemacolour Colour?

A LIVING! PICTURE \VO\T"DER. You've probably often asked yourself the above question while watching the natural colour pictures on the. screen, or at least you must have heard those about you speculating over the matter and probably offering various explanations-, ,'io Iwo 01' which agreed. First of all, the film used in making Kinemacolor pictures is made panchromatic, that is, sensil ised for all the rays of the spectrum. This peculiarly sensitive lilm is then exposed in the camera, behind a re- ! \oi\ing shutter in "which are fated two filters (or screens) coloured red and green. Thirty-two pictures a second are taken, alternately, through the red and green filters. This is the vital part to be remembered. "Ordinary white lightsunlight—contains all the colours of the spectrum blended together. The primary colours are red and gre-"u, and red and green light properly blended will give, any shade or. tint. fn exposing the film a red and a green glass (filter screen) an* brought in front of the lens alternately. The red filter allows only green light to pass through it, and one picture on the film is thus made with green i rays only. Next the green filter conies up into position, and this lets only red rays pass through, so the next picture on the film is made with red rays only. This is kept up as long as the shutter moves, the individual pictures on the film being' taken alternately with the green rays and the red rays reflected from the object photographed. After the positive print of the film has been completed we discover it to lie. apparently nothing but black and white, the same as an ordinary strip of film, but in reality all the tints, tones and shades of Nature are stored up within its depths. This film is run off. in the Kinemacolor projecting machine at the rate of .'32 pictures per second. Mere again the white light from the arc lamp is passed through similar red and green filters, which allow, respectively, only green and red rays to pass through. Consequently Die pictures thrown upon the screen are alternately red and green—at the rate of 32 per second. 111 other words sixteen pictures per second | are red and sixteen are green. So quickly do these pictures follow one another, however, that the eye cannot pick out the individual red and green ones, and fooled into believing that both reel and green are being viewed at the same instant. Since, as already stated, red and green light properly blended will give any shade or tint be-.' tween black and pure white, all the tints of the scene which lay bej fore the camera's eye. when the film j was exposed are in turn revealed to ours as we view the screen. Naturally. also, owing to the need J for projecting Kinemacolor-film at the I rate of 82 pictures a second instead of at the rale of sixteen pictures a. second, as in the showing | of ordinary black and while- pictures, the film has to be about twice the length of the black and j white subject. That is, if l,<ii>o, feet of film is necessary to tell a certain story in ordinary motion pictures, Kirueinncolor will require two full reels of l,(.)<)(i ,!'<>ct each ' to tell the same story.—"Popular Science Sittings."