Charles-François Daubigny was one of the painters of the Barbizon school, and is considered an important precursor of Impressionism. He was also a prolific printmaker, mostly in etching but also as one of the main artists to use the cliché verre technique. Cliché verre, also known as the glass print technique, is a type of "semiphotographic" printmaking. An image is created by various means on a transparent surface, such as glass, thin paper or film, and then placed on light sensitive paper in a photographic darkroom, before exposing it to light. This acts as a photographic negative, with the parts of the image allowing light through printing on the paper. Any number of copies of the image can be made, and the technique has the unique advantage in printmaking that the design can be reversed.