Images by photographer Shaun Irving, who has built the largest mobile camera in the world by constructing what is essentially a giant pinhole camera in the back of a moving truck. Light comes into the hole, and is projected through a lens onto 4-by-8-foot sheets of photo paper on the opposite interior wall of the truck.Read about the rest of the process at NPR's Picture Show blog and see more images at Irving's website, cameratruck.net.