Op Art and Blurred outline

This is the 2010 summer tour flyer the band Ominous Black used.  Their main picture at the top is Op Art. It's meant to trick the eye into believing that there is movement. We're drawn by the spiral into the center of the circle and triangle. The grid allows the illusion of distance and depth.

This is a photo of Touch and Taste perorming at the Tritone in Philadelphia.  The form of the bass and the performer are blurred.  The blue lights streak across the picture following the bassist from right to left.  This is a goo example of a blurred outline.