The Private Life of Plants
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An optical distortion device which can make a contact copy of a photographic film image with one dimension of the copy lengthened or shortened while the perpendicular dimension is unchanged is comprised of a pair of cylindrical motor driven rollers, at least one of which can be driven at a very low speed. The axes of the rollers are disposed parallel to each other and to a narrow slit through which a beam of light is directed. A copy sheet such as a photographic negative and a sheet of photosensitive material are pressed into intimate contact as they pass over the slit by a jet of positive air pressure and each sheet is held to the circumference of a respective roller by negative air pressure selectively supplied to a plurality of grooves in the surface of the roller. By varying the speed of one roller so that its rotation will be greater than, equal to or less than the rate of rotation of the other roller the dimensions of the image in the direction of movement can be made greater than, equal to or less than the dimension of the original in the direction of movement. An elongated light source is disposed beneath the narrow slit and a system of baffles and interchangeable light apertures are interposed beneath the slit and the light source to accurately collimate the light beam.