BORN FEB. 20, 1902, SAN FRANCISCO

died April 22, 1984, Carmel, Calif. photographer especially known for technical innovations and masterly representations of the dramatic sweep of mountainous terrain. Originally a student of music, Adams pursued photography as an avocation until 1927. In that year he published his first portfolio, Parmellian Prints of the High Sierras, photographs in the style of the Pictorialists, who imitated Impressionistic painting by suppressing detail in favour of soft, misty effects often achieved in the darkroom. In 1930 Adams was so impressed by the U.S. photographer Paul Strand, whose photographs emphasized beauty of tone and sharp detail, that he adopted Strand's approach, called "straight photography." With Willard Van Dyke, Adams in 1932 formed Group f.64, an association of photographers who used large cameras and small apertures to capture nature's infinite variety of light and textures. Holding as paragons the crisp brilliance of daguerreotypes and the landscapes of the 19th-century photographers Timothy H. O'Sullivan and William Henry Jackson, Adams became one of the outstanding technicians in the history of photography. In 1935 he published Making a Photograph, the first of many books on photographic technique, illustrated with reproductions of his own prints. In 1941 Adams began making photo-murals for the U.S. Department of the Interior. Forced by the large scale of this work to master the light and space of such immense landscapes as "Moonrise, Hernandez, New Mexico" (1941), he developed the zone system, a method of predetermining precisely what tone each part of the scene to be photographed will produce in the final print. Throughout his career, Adams worked to increase public acceptance of photography as a fine art. In 1940 he helped found the world's first museum collection of photographs at the Museum of Modern Art in New York City, and in 1946 he established at the California School of Fine Arts in San Francisco-the first academic department to teach photography as a profession. An ardent conservationist since adolescence, Adams served from 1936 as a director of the Sierra Club. Many of his photographic books, such as My Camera in the National Parks (1950), This Is the American Earth (1960), and Photographs of the Southwest (1976), are collections from the years he spent photographing the wildernesses of the United States, and are pleas for their preservation. Several general anthologies of his work, including Ansel Adams: Images, 1923-1974 (1974) and The Portfolios of Ansel Adams (1977), have also been published.