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Eye to Brain Connection

The human eye-to-brain connection processes rapid, sequential images into a constant motion effect, with imperceptible flicker, at a threshold of around 15 images per second. The brain's impression of a static image is ten times stronger than its impression of movement. Successfully smooth motion picture projection matches these limits of the eye in image speed and persistence of vision.

Jenkins' first camera/projector, a hand-cranked machine, simply passed the unexposed film from reel to reel and the film was exposed through a fixed aperture and a lens arrangement. To view the positive film, the system was simply reversed with an arc lamp placed behind the film, the reels set in motion at the same speed as the original recording, and the image viewed through the aperture or projected onto a small screen.

Animated Pictures
"Animated Pictures,
An Exposition of the Historical Development of Chronophotography, its Present Scientific Applications, and Future Possibilities...," 1898. (590K)
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Picture Ribbon Apparatus
Picture Ribbon Apparatus, no date. (1.3M)
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