"You think I'm mad don't you?" I ask this young woman. She laughs and nods. I am projecting a slide of a city scene onto a wall. As I stare at it, it seems to spring to life like watching an image in a Camera Obscura where the most bland scene becomes enchanting. "If you concentrate, the same thing will happen for you," I say. She shrugs and laughs again. She's not really interested.