critical principles: camera obscura image projection and the observation that some substances are visibly altered by exposure to light. There are no artifacts or descriptions that indicate any attempt to capture images with light sensitive materials prior to the 18th century. Around 1717, Johann Heinrich Schulze captured cut-out letters on a bottle of a light-sensitive slurry, but he apparently never thought of making the results durable. Around 1800, Thomas Wedgwood made the first reliably documented, although unsuccessful attempt at capturing camera images in permanent form. His experiments did produce detailed photograms