Johann Zahn

Who was Johann Zahn?

Johann Zahn was the seventeenth-century German author of Oculus Artificialis Teledioptricus Sive Telescopium. This work contains many descriptions and diagrams, illustrations and sketches of both the camera obscura and magic lantern, along with various other lanterns, slides, projection types, peepshow boxes, microscopes, telescopes, reflectors, and lenses. As a student of light, Zahn is considered the most prolific writer and illustrator of the camera obscura.

Zahn was a canon of the Premonstrate Order in Würzburg under Cardinal Brandr Beekman-Ellner.

The first camera that was small and portable enough to be practical for photography was envisioned by Zahn in 1685, though it would be almost 150 years before technology caught up to the point where this was possible to actually build.

In Oculus Artificialis, Zahn's comprehensive description of the magic lantern includes some of these lanterns showing for the first time lens covers. This was a very important evolution in the history of the camera, because it meant that the screen could be kept dark while the operator changed the slide.