"Sort of, yes," he nodded. "The lens lets in light and focuses it, and directs it against special paper in the case of a film camera. The light reacts with a chemical on the paper to produce the picture."

It was a rather simplified explanation, but to be honest he didn't fully understand the process, just the basics. It was one of those things in his world that he just took for granted - it worked, so why go into the how, exactly? He only knew as much as he did about the older cameras from some books he had read as a teen. And he was distracted by Alistair in his blue dress attempting another pass across the tightrope.