3D Hollow Face Illusion with Rolling Eyes (physical / no computer graphics)

This is an updated shorter version of the 2008 YouTube video under the title "3D face optical illusion: Rolling eyes on hollow mask". Improvement: I edited the video so that the mask ALWAYS rotates in the SAME direction (clockwise as seen from above). This makes it easier to appreciate the hollow-face illusion. Also, I give credit to artist Robert Bunkin, who painted the mask [winner or the 2008 Best Illusion of the Year contest (third place)].