The international photographer (Feb-Dec 1929)

Six The INTERNATIONAL PHOTOGRAPHER July, 1929 Ui ta co lor In the research leading up to the development of Vitacolor, the Electromagnetic theory of light and the phenomenon of the dispersive power of light have been utilized to a great extent. The mechanical action of the Vitacolor filter could easily be compared to a wireless receiving station which is tuned to respond to the various wave lengths. The Vitacolor filter is constructed also to receive the various wave lengths composing the natural colors. In nature each color is a combination of wave lengths and any object has a selective power of reflection. This means that when light reaches the surface of an object susceptible of reflection, which is the rebound of light-waves from the surface on which they are incident, it either penetrates beneath the surface or it rebounds directly from the surface with more or less absorption, so the degree of coloration of the object depends on the amount of rays partially or totally absorbed by the object. This mechanical action of absorption and reflection of rays of different wave lengths shows clearly that any natural colors formed in nature are always the results of more or less intricate combinations of different wave lengths. The Vitacolor filter has been de signed to transmit on the panchromatic emulsion an emission of vibrations similar to the multiple rays refracted by colored objects. The main features of the Vitacolor filter reside in what is known as fusion bands, control or tuning areas. The action of the control or tuning areas depends directly upon the nature of the wave transmitted by the adjacent filters and the fusion bands produce compounded series of vibrations in harmonic progression, which add to the delicacy of the half tones, while the control or tuning areas correct the unequal factor of transmission of filters used in color photography. One of the advantages of the Vitacolor filter is to permit quite short exposures. For instance, an ordinary exposure of a scene by the sea, in good light, which would be F-16 for black and white pictures, would be F-ll for Vitacolor. Pictures can be taken under practically the same light conditions which prevail for good black and white work. Scenes have been taken in early morning with high fog obscuring the sun, resulting in studies resembling the soft color tones of the old masters. No special fast lens is required, and any regular lens employed for taking black and white motion pictures will give excellent results. Special Vitacolor attachments are fitted to standard cameras and projecting machines, with a slight alteration which in no way impairs the effectiveness of the machines for regular use in taking and showing black and white pictures. Innumerable prints may be made from the original Vitacolor panchromatic negative, also reduction from standard 35 mm. negative to 16 mm. print without any loss in color rendering. After a demonstration of Vitacolor anyone with a knowledge of color photography will be convinced that the Vitacolor process is not solely concerned with the transmission of single color values, as such, to the emulsion of the film. What really takes place is to record the composite color vibrations on the panchromatic emulsion in substantially the same manner and condition as they are registered on the retina of the human eye. All of the conditions which attend the natural transmission of color vibrations are preserved intact so far as is possible. This is necessary if the result is to appear natural on the screen because, in the dark projection room, nearly all natural conditions are perforce removed, and if they are not carried throughout the process of color photography intact, they are not exhibited on the screen. ^BHSHSHHISHISIISHIM^^ ! EXPANSION I giSKHHllIJSSHIllllSII!^^ AX B. DU PONT VITACOLOR CORPORATION. 2079 North Occidental Blvd., Los Angeles, Calif., announces that Will H. Howse, General Manager, has gone to New York City to open an Eastern Branch of Vitacolor for the purpose of convenience in handling the rapidly increasing business of the company in that section. Important supplementary announcements will be made in The International Photographer for August. m 1 ,-!| 1 ||jH5]|!HBH!lSS!l![IKHHHH^ I VITACOLOR I lilHIllSigiglllllj®^