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

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In Aristotle’s book titled Problems there was described the phenomenon of sunlight passing through a square hole and still casting an image of a round—not square—sun on the wall or floor.

This was an astounding discovery! It may strike the reader as strange, but he may easily convince himself by making a little experiment: cut a square hole in a piece of dark paper and let the image of the sun fall on a mirror or other smooth surface and you will see that the sun is still round despite the square hole. As a word of caution, one must be careful to avoid eye strain when viewing the sun and its reflections. Several of the principal characters in motion picture pre-history ruined their eyes by studying the sun for too long a period at one time.

Aristotle’s square hole and round sun experiment was a beginning and scientists were starting to learn something important about light and optical phenomena.

Aristotle also made a valuable contribution to the study of vision. In his book, On Dreams, he noted the existence of after-images, a persistence of vision phenomenon. That faculty contributes vitally to the motion picture effect. A common example is that a whirling firebrand appears to make a complete continuous circle of fire. A strong light or image of any kind will be visible to the eye for a moment after the physical stimulus has been removed.