GB660994A - Improvements in or relating to stereoscopic reproduction - Google Patents

Abstract

660,994. Stereoscopic photography. ROGERS, G. L. April 8, 1949 [April 29, 1948; June 25, 1948], Nos. 11802/48 and 9538/49. Classes 97 (i) and 98 (ii). An anaglyph for the subsequent stereoscopic presentation of an object in colour comprises at least three positive images of the object in superposed and substantially registered relationship, one of said positive images being representative solely of the blue-coloured components of the object as seen from a first view point and dyed or printed in yellow and the other positive images being representative of the other coloured components of the object as seen from a second viewpoint and each being dyed or printed in a colour complementary to that of the colour component it represents. Such an anaglyph may be formed by exposing, in a stereoscopic camera 10, Fig. 2, a bipack 16 to light passing through a yellow filter 14 and a lens 12 and another film 15 to light from a lens 11 and a blue filter 13. The emulsions of the bipack are sensitized respectively to the red and green colour ranges and a filter passing only light to which the rear emulsion is sensitive is inserted therebetween. Colour separation positives of the images of the red, green and blue components of the object 0 are then prepared and printed in cyan, magenta and yellow respectively. These positives are superposed and, when viewed with a blue filter over the left eye and a yellow filter over the right eye, a stereoscopic effect is obtained. The yellow filter over the right eye may be omitted. A single lens camera may be used, two or more images being taken with the camera in one position and the image of the blue coloured components of the object being taken with the camera in a second position at a distance from the first, equal to the interocular distance. The filters 13, 14, Fig. 2, may be omitted when colour films 15, 16 are used, the required colour separation positives of the red, green and blue coloured components of the object being obtained by known methods. Alternatively, a camera as shown in Fig. 6 may be used. The lens 21 of this camera has associated therewith a blue filter 22 whereby the blue coloured component of the object as seen from a left eye viewpoint are recorded on a film 23, and lens 24 has associated therewith a beam splitter 25 whereby some light passes through a green filter 29 on to a film 27 and the rest passes through a red filter 28 on to a film 26. Again, an anaglyph may be produced using a single lens camera and a colour film by placing in the front of the lens a beam recombining device of the double prism type through which is transmitted a beam from the object after passing through a blue filter and by which is refluted a beam from the object after passing through a yellow filter and a prism disposed to one side of said beam combining device. The colour separation images may be provided on separate transparent sheets which are relatively slidable in parallel planes so that the registration of the images may be varied if desired.