The Kaufmann Posographe was not something I was looking for. In fact, I had never heard of it before buying. The opportunity to purchase it came from a contact at a local antiques mall, and I couldn’t pass on it.
Designed and manufactured in the early 1920’s, the Posographe uses a collection of seven interconnected sliders and associated cams to calculate exposure time. Exposure is calculated using factors such as indoor/outdoor, time of year, type of landscape, weather conditions, aperture, the sensitivity of the film emulsion, etc.
This image is from the original manual and shows the internal mechanism.
Categories: Exposure Calculator