Читать книгу Magic Shadows. The Story of the Origin of Motion Pictures онлайн

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A detailed and rather technical explanation of how the camera system works was given by Kepler. Towards the end of the description he wrote an important instruction: “All the walls of the camera except the one used as the screen for the images should be black.” This was necessary to prevent reflection and dulling of the brilliance of the images on the white wall or screen. Everyone knows how the insides of a modern camera are black for the very same purpose. Kepler also noted that the “camera” must be tightly sealed. He was the first to refer to the device under the simple name of “camera” which in time was adopted universally.

Kepler also was the first to give a sound theory of vision. (Recall the shot-from-eye or shot-from-object schools of the ancients.) Kepler stated, “Seeing amounts to feeling the stimulus of the retina which is painted with colored rays of the visible world. The picture must then be transmitted to the brain by a mental current and delivered at the seat of the visual faculty.” That is a rather good definition even by modern standards. Kepler, however, was not 100 per cent correct. He held that light had an infinite velocity. To Kepler goes the credit for being the first correctly to explain after-images, a knowledge of which is so vital to understanding how the illusion of motion is created.