COLOUR PHOTOGRAPHY

Greymouth Evening Star, 21 April 1938, Page 14

COLOUR PHOTOGRAPHY

REDUCING THE COST. The day must not be far distant when any photographer will be able not only to take coloured snaps on film or plates, but may make as many coloured prints on paper as he desires at a cost within reach of the ordinary amateur, says the ‘News Chronicle,’ London.

At present the process is so long and costly as to be beyond the pocket of the average photographer. A colour print now costs anything from 10/- to £5 5/-,. according to the size. Mr. A. von Bariss, a 53-year-old Viennese photo-chemist, claims to have perfected a method by which he can take, develop, and print a colour picture in 90 minutes at a total retail cost of 1/6 for a 4.1 by 3Jin. print. Further prints can be run over every 45 seconds for 4d each. Mr. von Bariss claims that the speed of his developing and printing methods, plus the use of a colour-cinema camera which he has invented, makes it possible to take colour films and show them in an unlimited number of cinemas on the same day. The process, which has taken Mr. Bariss nine years to perfect, is a secret one. It depends on the chemical reaction of certain emulsions on a special kind of printing paper.

Board of Trade officials know of the process, and Mr. Bariss has been given permits to import the necessary dyes and to remain in this country to continue his experiments. In his laboratory in the city Mr. Bariss explained his process to the ‘New Chronicle.’ THREE PICTURES TAKEN. With a special camera containing three filters —yellow, red, and blue — he simultaneously takes three pictures of the image on ordinary colour sensitive (panchromatic) film. One picture registers yellow light, another red, and a third blue. These he calls “separations.” From these “separations” Mr. Bariss makes three celluloid matrices. Working in daylight, he placed a piece of his special printing paper on a small hand press. Dipping the yellow matrix made from a photograph of a bunch of multi-coloured carnations into an emulsion, he laid it over the printing paper and pressed it like a transfer.

He counted up to 10, then whipped off the transfer, and a skeleton appeared in yellow on the paper. Repeating this with red and blue matrices, in 20. seconds he had produced a paper picture of the bunch of carnations in shades of red, orange, magenta, green, blue, white, and the elusive black which colour photography experts have so far failed to produce.

With a camel-hair brush dipped in various solutions Mr. Bariss deftly retouched the picture, making colours disappear or reappear at will. | Three hundred prints can be made 'from one set of matrices, and without the aid of his three-filter camera Mr. Bariss can make an equal number of prints from any commercial colour film taken with any ordinary camera. For still pictures the shortest exposure given by Mr. Bariss in exceptionally good light is l-75th of a second with a 4.5 lens. He works at 1-25 or l-35th of a second in normally good light. ' The process differs from others in that it does not need a special apparatus to, reveal the colours.