One of the basic elements of the moving image is the light source and a current exhibition at the San Francisco Museum of Modern Art, 'Project, Transform, Erase' takes this simple element as its theme. Filmmakers Anthony McCall (American) and Imi Knoebel (German) both use the physical properties of projected light to create and illuminate architectural spaces. McCall's new work, entitled 'You and I, Horizontal' is comprised of two projectors and a fog machine which combine to create a three dimensional space in which the viewer can observe and manipulate the power of light to convey space. In Imi Knoebel's work, 'Projektion X,' originally made in 1971-72 (and remade in 2005 as part of a preservation initiative at ZKM under the curatorial eye of Rudolf Frieling, now at SFMOMA), uses an X-shaped beam of light to illuminate urban architecture. Driving around the city of Darmstadt, Germany, the filmmaker projected this simple geometric form onto the streets-capturing an abstract portrait of the buildings around him. 'Project, Transform, Eras' is on view through September 30th. - Caitlin Jones