The Hollow-Face Visual Illusion in Digital Technology (2009)
Illusions have always been a fascination for mankind. The history of illusions dates back to Aristotle, who described a tactile illusion occurring when one crosses two fingers and rolls a ball in between ones two fingers. In the well known hollow-face illusion, a hollow (concave) mask of a face appears convex and to follow the observer.
Effects of Shading, Texture, Movement, Noise and Scenery
For his graduation thesis entitled "Effects of Shading, Texture, Movement, Noise and Scenery on the Hollow-Face Visual Illusion", international student Dünya Kırkalı researched how different visual presentation conditions of the hollow face affect the strength of the illusion. With the use of modern digital technology, he set up experiments to study how people experienced the illusion.
For this, he made a 3D laser-scan of his own face, from which a semi-transparent 3D mask was created. Dünya then experimented by projecting static and dynamic digital images onto the hollow-face, while varying visual conditions that may affect the strength of the illusion. These varying conditions were shading, image noise, scenery, facial movement and texture. From these experiments it was discovered that texture and image noise significantly impact the strength of the illusion.
The setup created for the experiments was fascinating to experience, with its strong dynamic visual illusion. It was exhibited as a scientific artwork at the "Discovery 09" festival organised by NWO.