Hurter & Driffield... Actinograph
By: cshimokita : July 19th, 2019-16:37
In 1888, Ferdinand Hurter and Vero Charles Driffield patented the "Actinograph", a device for computing exposure times and apertures for cameras. It didn't measure anything, and was more like a slide rule based on the plate speed, time of day, time of yea...