GB319660A - Method of printing films with sound and picture records and apparatus therefor - Google Patents

Abstract

319,660. Electrical Research Products, Inc., (Assignees of Coffman, J. W.). Sept. 25, 1928, [Convention date]. Combined sound and kinematograph records. -In printing a positive film from a single negative film which has both sound and picture records thereon, provision is made for filtering the printing ligh directed on to one or both of the records so as to obtain a differential overall contrast between the printed sound record and the printed picture record. This may be effected by incorporating a dye in the positive film emulsion and directing the light for printing the sound record through a filter of a complementary colour. To enhance the contrast in the picture record, the light for printing this may be directed through a filter of the same colour as the dye. Apparatus for printing comprises sprocket rolls for feeding the superposed films between a pad 7, Fig. 1, and a mask 6 adjustable vertically in relation to the printing light 5 to position any one of three apertures 8, 9. 10, Fig. 2, in the light path opposite to an aperture in a back plate 11. The aperture 9 covered by a suitable colour filter is positioned for printing the sound record alone, and the aperture 8, covered if desired by a suitable colour filter, is positioned when the picture record alone is to be printed. The aperture 10 is provided so that the apparatus can be used for printing ordinary full size picture records without a sound record thereon.