anamorphosis
The Ambassadors, 1533
Hans Holbein the Younger
In the artistic technique called anamorphosis, an object is depicted in distorted perspective, so that the viewer has to take special action, like looking from a specific angle, to see the "correct" image.
The most famous example of anamorphic painting is Hans Holbein's The Ambassadors (1533), a double portrait in which the illusion of highly detailed reality is fractured by a blurred grey streak superimposed across the painting's bottom third. If one stands at an acute angle, close to the painting, the blurred streak resolves itself into a…