POSTAGE STAMP PHOTOGRAPHS For producing these professionally, a camera containing a battery of small lenses may be used, its interior being partitioned into as many sections as there are lenses, thus securing a number of images on one negative. The illus tration shows a camera for taking nine photo graphs on a quarter-plate. The back of the camera has brass plates A to take the dark-slide ; the front is at s ; and an easel for supporting the original photograph at c. The box is 6 in. by 5 in., its depth depending on the focal length 9f the lenses used. For a one-third scale reduc tion, as in reducing a quarter-plate original to one-ninth that size, the distance between lens and plate will be the focal length of the lenses plus one-third that focal length ; the result multiplied by three gives the distance between lens and copy. Thus, with a 3-in. focus lens, 3 + 3= 4 •, the distance between lens and plate ; while 4 x 3 = 12 in., the distance between lens and copy. The divisions are of blackened wood or cardboard partitions.
In the front, but not illustrated, are circular openings to take the nine small lenses, and the hinged shutter D is worked by the projecting rod E. The box is attached to a baseboard F. Pinholes could be used instead of lenses, but the exposure would be greatly prolonged.
The camera can be adapted for direct por traiture by providing focusing adjustment, and omitting the easel. Printing from a negative produced in this camera can be done in an ordinary printing frame, using a suitable mask and a multiple border negative for producing the stamp effect. The perforations are done by a special machine, after the backs of the sheets have been brushed over with dextrine and allowed to dry.
In the absence of a special camera, a succession of images can be printed on a single sheet of paper, using a repeating printing frame, and the result may, or may not, be copied in the camera to produce a negative from which a large number of images can quickly be printed.