Kaufmann’s Posographe: An Amazing Exposure Calculator from the 1920s

Kaufmann’s Posographe is an intricate pocket-sized mechanical calculator invented back in the 1920s. Measuring 13x8cm and filled with tiny scribblings, the device allowed photographers to approximate the exposure values they needed by simply sliding around six small pointers.

Here’s a look at the front and back of the Posographe, along with a diagram of its innards:

Technology has come quite a long way since then, eh?

Kaufmann’s wonderful Posographe [History of Computing]

  • Spider- Man

    I still use that paper slider…

  • Spider- Man

    this one

  • RazorbladeGrin

    I know it’s silly, but I would love to see an exposure app with that graphical interface & animated sliders…

  • Sam

    seems an iPad conversion would be fairly straightforward :)

  • GottaWanna

    If I could get one, I’d use the brass one, in all its steampunky glory!

  • Jay Lee

    I found one in a shop in Paris. I have uploaded some detail shots of the device to my Flickr stream. It really is quite a brilliant apparatus