Broadcasting Telecasting (Jul-Sep 1954)

LIVING and LEARNING WITH COLOR TV WHAT WTMJ-TV FOUND OUT ABOUT USING THE COLOR DIMENSION by John Colby Lewis WTMJ-TV MILWAUKEE was one of the first stations in the country to bring in color television equipment after the FCC approved compatible standards last December. Using that equipment in the succeeding months has been largely a matter of trial and error for the production and engineering staffs. What they learned was compiled by Mr. Lewis, assistant program manager, in a summary for producers and directors. BST submits his information as basic reading for anyone who is going to handle tv's newest technique. LIGHTING: Color fidelity depends on enough light (300 to 400 fc) evenly applied. The amount of light reaching the camera tubes is regulated by an iris control at the video control console. Colors change as this iris is opened and closed. If the illumination on the brightest areas of a scene is just enough for faithful color reproduction with the iris wide open, the color of darker areas is bound to appear false since the iris can be opened no farther to expose them properly. The color of a subject changes perceptibly as it moves through hot spots and shadows, which unless motivated should therefore be evened out. The unevenness may be caused not only by direct light but also by bounce light from some reflectant surface. In judging the light distribution, a meter is more reliable than the eye. The color of the subject also changes as it moves along a horizontal light beam, either towards or away from a close-at-hand source. Overhead lights should therefore be beamed in at no angle flatter than 45 degrees. If floor spots are used, they should be on as high stands as possible and at some distance from the person walking towards them. To adequately light a given playing area takes not only the sources immediately above it but also as many as three rows of overhead lamps downstage of it. This means that you cannot light the whole studio to a level sufficient for color pickup. Playing areas must be restricted in size and located with reference to light positions. Spots on floor stands, panning with the action, have proved helpful in reinforcing insufficient light levels. Care must be taken, however, that they move with the camera so not to unbalance the evenness of the illumination. Backings need as much light as performers in order to establish their true color. Under insufficient light they may mottle with tinges of spurious colors, as is the tendency with underlighted areas. Back light is as effective in color as in monochrome. Because of the intense front light, backlight spots need either to be focused down or supplemented to develop sufficiently snappy rim lighting. Back light is effective for enlivening bottled liquids, especially if in dense containers. Tests have indicated the possibility of tinting neutral backgrounds such as gray drapes with colored light from scoops and spots equipped with gelatine and from striplight sections. We also have tried colored light on the back of the rear projection screen. In both instances, the white light used on the playing area must be prevented from washing out the colored background light, both by bringing performers out at least eight feet from background and by lighting them from a fairly steep angle. It is difficult to color a background evenly because light that rakes it shades off rather sharply. The amount of light required for color pickup creates glare that may trouble performers' eyes, and heat that may exhaust them if they are not given sufficient respite from it. Perspiration may quickly bring back shine to powdered faces and even show through pancake makeup, looking like blisters. ENVIRONMENT: The color of the subject is affected by that of surrounding and background areas. Thus the color of skin and clothing may change as a performer moves from one background to another, particularly if these backgrounds differ widely in value (the amount of light they reflect). It is safer to keep backgrounds fairly plain and uniform, not only to avoid the result just mentioned, but also because color is of such interest itself that too much additional detail will make a confusing picture. Still, one must maintain enough value variations to keep the black and white picture interesting. Large, glaring white, or extremely light areas of background or costume darken the tones of everything nearby and thereby change its hue. That makes them a poor environment for subjects where color fidelity must be maintained, such as flesh tones and commercial products. To play safe, use backgrounds a shade or two darker than the subject. For darkening a backing without repainting or substituting a new one, you may be able to move a light off it, or to move it back, angle it down, or shield it so that it receives less light to reflect. Reflectance, incidentally, plays a substantial part in color appearances. The appearance of glossy surfaces is sometimes hard to predict. For example, a "desert rose" seamless paper may register as a near white owing to the way it reflects light into the camera. For the same reason, shiny faces may look pallid. Glitter is no problem, however; jewelry and band instruments produce no black halo as in monochrome. Almost always, backgrounds need to be more desaturated than the subject of interest so that they will not overpower it. In some cases, materials that seem dull to the direct observer will prove too bright on camera. Thus blue will generally come through stronger or more "electric" than one would expect. On the system, as elsewhere, warm colors advance; the hotter, the more so. Hence avoid strong reds, oranges, and yellows as background or in accessories where they will detract from the center of interest In making a subject stand out from its Page 70 • August 23, 1954 Broadcasting • Telecasting