India, July 24 -- "Travel becomes a strategy for accumulating photographs," the American essayist Susan Sontag wrote, in 1977. "A way of certifying experience, taking photographs is also a way of refusing it-by limiting experience to a search for the photogenic, by converting experience into an image, a souvenir."

The camera has, for centuries, been something of a disruptor. But it started out quite differently: as the science of understanding how certain chemicals and materials responded to light.

When Frenchman Nicephore Niepce took the first photograph, in 1826, it was a process that required hours of exposure. It was a scientific miracle: A picture drawn by light itself. (Those hours of exposure, in fact, meant that early images cou...