Anamorphosis: a painting or drawing that is distorted or unrecognizable except when viewed from a particular angle and distance or with a correcting mirror or lens; also, the technique by which such an image is drawn (see DIY instructions). Normal images are composed for a viewer’s gaze and consist of only two coordinates: the vertical surface of the image and the orthogonal line. In anamorphic images there are three coordinates: the vertical, the horizon, and the oblique line from the diagonal corner to the image (see list of links). In general, a distinction is made between cylindrical anamorphosis and perspective anamorphosis.

Perspective anamorphic image:
a classic example is Hans Holbein the Younger’s painting "The French Ambassadors," painted in 1533. As soon as you look at it from the side, the strange thing in the lower foreground between the two figures appears to be a death’s head. See also: Grubinger’s #2: Black Out, #3: Team Bullying, or #4: Corpus Modulare.

Cylindrical anamorphic image:
in a cylindrical anamorphic image, a cylindrical mirror, or sometimes a type of vase, is placed upon the picture in order to reveal the distorted surface. See Grubingers #1: Generation Gap.

Download DIY-Anamorphosissoftware for Windows

Program for Creating Your Own Anamorphic Effects; (Pfaffenhofen, 1999)
Final project for a secondary school degree by physics major Friedl Ulrich, second-prize winner of the "Youth in Research" competition for secondary school students.