Anamorphosis has been present in art for centuries; the anamorphic skull in Hans Holbein’s The Ambassadors is a well known example. More recently, fleeting 3D sidewalk art has sprung up across the globe, capturing the imaginations of passersby who can’t help but stop and snap a photo of a friend seemingly teetering on the edge of oblivion or about to be swallowed by a shark.
One method of creating anamorphic images relies on projective geometry, specifically a central projection, to map points from a 3D object to their corresponding locations in the 2D anamorphic projection. The Anamorphic Projection Stand (APS) is a simple tool we created for making small scale, desktop anamorphic projections. The APS consists of a stand, a view finder, and a projection line. The projection line extends from the center of the eye hole in the view finder; the center of the eye hole serves as the center of projection. The projection line, in this case a piece of yarn, creates a physical mapping that extends from the center of projection, through a given point on the 3D object, then back down to the table where the projected point lives. By carefully and strategically mapping points from the 3D object down to the table top one can construct an anamorphic image of the 3D object.
A few important considerations:
The entire system must remain static, with the exception of the projection line, while creating the projection. That is, the center of projection must remain in the same place for each projection, as well as the 3D object. The 3D object can be moved only if it is returned to its exact same position for the next projection (be sure to the mark points on the base of the object).
Anamorphic images will only appear 3D when viewed precisely from the center of projection (note the boy looking through the view finder above). This doesn’t mean you must look through the eye hole to get the 3D view, just make sure you take note of the height of the center of projection, and the distance from the 3D object to the center of projection.
Written by Bohdan Rhodehamel
Contact Bohdan at firstname.lastname@example.org