Camera Obscura, San Francisco

This San Francisco landmark was built to resemble a vintage camera, but the origins of the camera obscura are far older than modern photography. Leonardo da Vinci outlined the principles governing it in the 16th century. Visitors enter a darkened, hushed room where the walls are lined in black velvet and holograms. In the center is a bowl-shaped screen, 3 1/2 feet in diameter. Using mirrors and lenses, a living image of the surrounding ocean and beach are projected onto the screen. The difference between seeing that scene outside or seeing it on the camera obscura is the difference between reality and a dream.