Ansel Easton Adams (February 20, 1902 – April 22, 1984) was a landscape photographer and environmentalist known for his black-and-white images of the American West. He helped found Group f/64, an association of photographers advocating "pure" photography which favored sharp focus and the use of the full tonal range of a photograph. He and Fred Archer developed an exacting system of image-making called the Zone System, a method of achieving a desired final print through a deeply technical understanding of how tonal range is recorded and developed in exposure, negative development, and printing. The resulting clarity and depth of such images characterized his photography.
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I have often thought that if photography were difficult in the true sense of the term -- meaning that the creation of a simple photograph would entail as much time and effort as the production of a good watercolor or etching -- there would be a vast improvement in total output. The sheer ease with which we can produce a superficial image often leads to creative disaster.