The Leica Tandem is the invention of Mr. Wini Berssenbrugge, internationally known Dutch specialist in color steieo photography with the Leica Camera. The prototype was developed for work at the K. L. M. Airlines Technical College, where title program of visual education for engineering students demanded the production of many thousands of Leica Photograph -- chiefly of complex engine mechanisms and structural features of aircraft. As the majority of the photographs were required for projection purposes, the stock of teaching slides was build up to in include both 35mm black and white and color transparencies.
Originally, the Tandem was designed for use with a pair of Leicas and 50mm lenses--for stereoscopic photography, and although stereo work was limited to shots with vertical composition, this was not considered a disadvantage; for the color work at the college was confined almost wholly to recording vertical panels of lexer control mechanisms. In the final projection of the stereo color pairs (by the Leitz “Stereoly-Polaroid” two projector system), the three-dimensional depth, and distance apart of the lexers and gears was readily appreciated by the students, each of whom wore “Polaroid” spectacles.
Excellent though the Tandem is for Leica stereoscopy, we know that it will have a much greater appeal to the advanced Leica Photographer for simultaneous black and white and color photography. Magazine photographers, for example, are often required to submit to art editors a selection of both types of photographs — the reason for this being that the high cost of color reproduction often limits the number of color shots an editor may use to illustrate a given story, and the black and white shots, which are necessary for continuity, are, of course, cheaper to reproduce. The use of the Tandem obviates making monochrome negatives of selected color shots, as, it' it is desirable, any one shot can be secured in both color and black and white, at the same instant.
The flexibility of the Tandem is one of its chief attractions--for, since the shutter of the top Leica may be wound, set, and released independently of the lower Leica, the photographer is not tied down to duplicating every exposure on black and white, and color film. For instance, assuming that he intends to shoot more monochrome film than color, then the lower Leica is loaded with color transparency film and the top with negative film. When duplicate shots arc required--he winds both shutters with the Tandem coupling knurl: for a single shot, he winds only the top Leica.
The speed and ease with which the Tandem-coupled Leicas may be separated, and either Leica used individually—without adjustment--is further demonstration of the Tandem's flexibility: when the two cameras are to be connected together again, it is necessary only that they be loaded and wound, in addition, the Tandem baseplate has a built-in bushing, so that if it is desired, the top Leica (to which the baseplate is fitted) may also be used separately, on a tripod.
The sequence of operations when using the Tandem is easily followed. Assume that: a monochrome film, such as Kodak Panatomic-X, which has a Weston speed rating of 24, is loaded in the lop Leica, and that the shutter is wound: that Kodachrome Daylight Film, with a Weston speed rating of 8, is in the lower Leica, and that the shutter is also wound. The exposure ratio of these films is 1:3, so therefore, the shutter speed dial of the lower Leica (which cannot be altered while both Leicas are coupled) should be set at, say, 1/60 of a second. the shutter speed dial of the top Leica (which can be altered while both cameras are Tandem-coupled) should then be set at 1/20 of a second--thus maintaining the ratio of 1:3--whereby, the lens diaphragm setting of both Leica Cameras remains constant, at ƒ3,5, ƒ6,3 or whatever aperture the exposure meter indicates. When the lens on each camera is of 50mm, focal length, it is not essential to use an Imarect Finder: compose the photo and bring it into focus through either the upper or lower Leica eyepieces. whichever is preferred, and set the focusing scale of each lens at the same distance marking. Having checked these important steps in the routine, and remembering that the shutter of the black and white camera has already been set at 1/60 of a second, shoot the photo by squeezing the release button of the top Leica firmly and steadily--whereupon the shutters of both cameras (having been factory synchronized by us) will fire in unison, capturing tile identical scene on both films.
To reset the cameras for the next "double take," wind both shutters by rotating the knurled winding collar of the Tandem. If, however, it is desired to photograph the next scene only in monochrome, then wind only the shutter of the top Leica, in the normal way, and ignore the lower, or Tandem winding collar. After one or more single shots have been made, one may go back to “double takes” without the slightest possibility of damage or strain on either Leica Camera shutter. Having started out with the intention of shooting more black and white than color, and having therefore loaded the upper camera with monochrome film (since the shutter of the top camera can be operated independently of the coupled lower camera), it will be necessary to uncouple the cameras from the Tandem, should the photographer now wish to shoot only in color.
When shooting with Tandem-coupled Leicas in a “fire one, fire two, fire one, fire one” fashion, the film in the top (“fire one”) Leica will naturally lie expended before the film in the lower Leica. The cameras must be uncoupled for unloading and reloading, as already stated--but if, say, ten exposures still remain on the film of the lower Leica, it is but necessary to reload the top camera, couple it with the lower Leica, and resume shooting.
If the photographer wishes to use lenses of different focal length--as, for example, the Elmar 90mm., ƒ4 coated lens and the Summitar 50mm., ƒ2 coated lens--it is still only necessary to range find with one lens and set the focusing scale of the second lens at the same calibration. Keep the Imarect Finder set for the 90mm. lens (adjusting for parallax at distances of less than 15 feet), and use the standard camera view finder for the 50mm lens. As shown in the complete set-up on this page--the Imarect Finder is also attached when other than the standard, 50mm focal length lens is employed. If any of the long-focus lenses are used in conjunction with the Elmar 35mm lens, then it is advisable to scan the wide angle view first, and to expose while viewing the narrow angle scene through the Imarect Finder.