Patent GB-717821-A (GB)
Title: Improvements in or relating to apparatus for ensuring registration in photographic reproduction processes
IPC: G03B27/72
Filed: 1949-05-04
Abstract: 717,821. Photo-mechanical apparatus. NICHOLLS, R. H., and STENT, A. H. Aug. 4, 1950 [May 4, 1949], No. 11926/49. Classes 98(1) and 98(2) For superimposing images of separate copy such. as line work or lettering in register, on to a succession of images as of colour separation negatives taken from a single original, apparatus comprises support members 1, 2 connected by parallel slide bars 4, 5; a carriage 6 in the form of an open rectangular frame slidable on bar 5 by lugs 7, 8 with a lug 9 resting on the lower bar 4 as guide during sliding and which carriage may be swung about the bar 5; a pair of apertured mounts 10, 11 mounted on the carriage 6, mount 10 having end plates 12. 13 connected by side rods 14, plate 13 being provided, below, with a lug for reception of pivot bolt 15 on the carriage 6, and, plate 12 above, with a slot 16 for screw 17, permitting angular adjustment; and clips 19 on transverse supports 20 for mcunting for example a lettering transparency, the supports 20 being slidable on rods 14 for adjustment to the size of the transparency. The apertured mount 11 has parallel side rods 23 slidable in holes in opposite flanges of the carriage 6, a transverse plate 24 between the upper ends of the rods 23. screw 26 with hand wheel 28 whereby mount 11 may be positioned vertically, and clips 30 on transverse supports 29 to hold. for example, a colour transparency. Screw stops 31, 32 adapted to engage lugs 7, 8 of the apertured mounts 10, 11 respectively enable the latter to be brought, successively, into identical position. In use the apparatus is set up in the optical axis of a camera, the carriage 6 is moved to the left as shown, the copy matter in mount 11 is focused on to a focusing screen, with enlargement or reduction if required, and stop screw 31 is adjusted to engage lug 7 and thus determine the leftward position of the carriage 6. A tracing of the image is made on the focusing screen and stuck down at each corner. Carriage 6 is then slid to the right, the line work or lettering transparency in mount 10 is adjusted to bring the image thereof into correct relation or register with respect to the tracing, and stop screw 32 is adjusted to abut lug 8 and limit the rightward movement of the carriage 6. Successive exposures if desired with use of colour filters. each with. the line or lettering image in register with the transparency image, may then be made by substituting a sensitive surface for the focusing screen and sliding the frame 6 to the left and right limits of the screw stops for each exposure. Colour correction. One or more masks such as a negative of the transparency may be placed in front of the latter during the whole or part of each exposure by mounting the mask in a hinged frame shown in Fig. 2 slightly open, and adjusting the mask (on plate 44) to register with the transparency when the frame is closed. If desired each of the mounts 10, 11 may be provided with such a hinged frame. The apparatus may be used in conjunction with that of Specification 717,872.