NATURAL COLOUR PHOTOGRAPHS.

Manawatu Standard, Volume XLIV, Issue 929, 30 January 1924, Page 10

NATURAL COLOUR PHOTOGRAPHS.

“ALL THE DIFFICULTIES SOLVED.” Producing direct colour photographs is the inte -esting hobby of Sir Charles Stewart l'orbes, who has certainly achieved seme remarkable results. “People have become tired of the sameness i f tho ordinary black and white photography,” he told the London Daily Sketch recently. “My ain over a great number of years has been to produce a photograph which gives direct colour without unduly long exposure or unnecessarily great trouble. The results achieved jmtify me, I think, in claiming that a;l the difficulties have been solved.” PLATE AND FILAI. An ordinary camera is used for the purpose, but two negatives are employed, one by a plate and the other a film. The film, which is placed in the dark slide in front of the plate, is sensitive to the blue-green rays, but unsonsitive to red; while the plate is sensitive to red. , t By means of a pink-coloured dye the film is given the properties of a light filter that tends to prevent any but the fed rays rea filing the plate behind. Best results are achieved in the studio where, under artificial light, the exposure required is only half a second or less. . , Two brom.de prints are made, ine first (from the red-sensitiye plate) is taken outran sfero paper, and on being stripped is placed on a piece of waxed ground glass before being toned a blue-re-een From the film a yellow-red print is obtained by the carbro process. While thei are wet the red print is super-imposed on tho green. They then dried and the prints come off the ground glass easily and form Hie finished picture in colour.