lightmeters

Devices intended to mesure or evaluate light conditions in order to assess aperture and speed for picture taking

Le Posographe | Kaufmann

–  Le Posographe | Kaufmann Inventeur-Constructeur | 1931 – This is a computer. It is, in the sense that you enter information on it; it performs some operations with that (real time in this case) and gives back a result that you can read and use. Every sliding rule or disks is also a kind of a...

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