THE KEOMSKOP OR PHOTO-CHROMOSCOPE.
The principle of the Ives Kromskop is illustrated by Fig. 576, which is a section through the apparatus. The pictures are corresponding transparencies. Compari son of these, one with another, will en able the principle to be readily grasped. For example, if a red glass were placed behind the red transparency, Fig. 573, it is clear that the only part which will suffer the red light to come through is the transparent portion of the shield, which, it will be remembered, is red in the original. Similarly, when a green glass is used for viewing the green trans parency, Fig. 574, only the ground will be .seen, the shield being represented by an viewed through the lens at A. The red glass and transparency are placed at e, the green at c, and the blue-violet at n. Reflectors of coloured glass, E a, are arranged so that they reflect the red and blue transparencies, but allow the green one to be seen through them. A nother plain reflector is placed at F, to throw light conveniently through the green transparency, 'and the angle of the in strument is provided for by a hinged strut fixed to the baseboard. The manner in which the light falls through the different parts of the apparatus is shown by the TEE KnomAz.
As a result of patents by Barnard and Gowenlock, an instrument known as the Kromaz has been lately introduced. While founded in principle on the Kromskop, dotted lines. The Kromskop is generally provided with two lenses, the pictures being taken in pairs, so that not only is a realistic effect of colour obtained, but the whole is seen with stereoscopic relief.
Mr. Ives has also devised a triple lantern and using the same colour screens, the apparatus is greatly simplified, so that only two, instead of three, pairs of stereo scopic images arc necessary. One picture with three lenses and coloured glasses, by means of which pictures in natural colours may be shown on a screen. Whether seen in the Kromskop or by projection, the photographs obtained by this process are extremely truthful and beautiful, although it must be admitted that they leave the problem of direct photography in the colours of nature, at one operation, still unsolved. It is unquestionable, however, that the inventor has contributed con siderably to the exact knowledge of the theory of colour.
is obtained through a blue-violet screen, one through a red, and two through green screens. This, of course, reduces the size of the plate necessary, enables the appara tus to be of simpler construction, and requires only one mirror instead of two. The instrument and accessories are shown by Fig. 577 ; A is a frame containing the three colour screens ; B is an attachment which fits into the camera back, carrying the colour screens and dark-slide when making exposures; while c is the viewing apparatus itself. The process can be worked with almost any quarter- or half plate camera having the focussing adjust ment in front.