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The ratio of a distance measured on a photograph or a mosaic to the corresponding distance on the ground. It is the ratio of the size of the image to the actual size of the object. It is very large scale when the ratio is larger than 14,999; large when it is from 15,000 to 109,999; medium when it is from 110,000 to 124,999; small when it is from 125,000 to 149,999; and very small when it is 150,000 and smaller.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved