Ansel Easton Adams (February 20, 1902 – April 22, 1984) was an American photographer and environmentalist. His black and white landscape photographs of the American West, especially Yosemite National Park, are the most well know. He published many books over his long career and was a contemporary of Georgia O'Keeffe, Alfred Sieigiliz, Nancy and Beaumont Newhall and Edward Weston.
Adams and Fred Archer developed the Zone System as a way to determine proper exposure and adjust the contrast of the final print. The resulting clarity and depth characterized his photographs. He primarily used large-format cameras because the large film used with these cameras (primarily 5x4 and 8x10) contributed to sharpness in his prints.