1906 article re Wollensak’s solution to media insensitivity to blue light
Toronto. … or so said Chicken Little in the Children’s fable (I learnt the English version … ). For many years film and glass plates were basically insensitive to blue light (orthochromatic) so clouds and sky exposed for the landscape came out as white (ie. severely underexposed). Some filters solved the problem with a half clear bottom and a yellow top.
Wollensak, in this article from the Amateur Photographer for January, 1906, came up with a novel shutter solution. Its ‘Skyshade’ shutter slowly exposed the sky at a varying speed while the landscape was exposed at an adjustable ‘fast’ speed. This was all done with the shutter mounted in front of the lens and the camera securely mounted on a tripod.
Our thanks to my good friend, George Dunbar, for sharing this historic article with us.
