PURPOSE: Distortion by a simple lens.
DESCRIPTION: Viewed from about 30 cm in front of a large diameter 20 cm focal length convex lens, the back edge of a matchbox about 10 cm behind the lens appears longer than the front edge.
For large groups, a TV camera is positioned about 30 cm in front of the lens, as in the above photograph.
REFERENCES: (PIRA unknown.) See Demonstration Reference File.
EQUIPMENT: Mounted large diameter 20 cm focal length lens and matchbox, with TV camera and lighting.
SETUP TIME: 5 min.
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