Eugene Ostroff, 71, longtime curator of photography and supervisor of the division of photographic history at the National Museum of American History, died of cancer Aug. 19 at Sibley Memorial Hospital.

Mr. Ostroff retired in 1994 after 34 years with the Smithsonian Institution. He was credited with opening the museum's Hall of Photography in 1972 and organizing numerous special exhibitions from the 1960s to the '80s, including important works by contemporary photographers such as Richard Avedon and Elliott Erwitt.

An authority and frequent lecturer on photographic history and technology, he led the effort to build the interactive Hall of Photography, which reviewed the history of photography from its invention in 1835 until the exhibition was opened. At the Arts and Industry Building, he produced displays featuring photographs by celebrated war photographer Robert Capa, photojournalist Arthur Rothstein and noted commercial photographer Victor Keppler.

Two of Mr. Ostroff's major exhibitions were circulated by the Smithsonian Institution Traveling Exhibition Service, "Photographing the Frontier" (1976) and "Western Views and Eastern Visions" (1981).

"During Ostroff's tenure as curator, he not only shaped the development of photographic collections at the Smithsonian, but he also influenced the way photography is viewed, collected and interpreted nationally," said Lonnie Bunch, associate director of the Smithsonian.

A Washington resident, Mr. Ostroff was born in New York. He received degrees in photography from Los Angeles City College and New York University. In the 1950s, he took graduate courses in photographic engineering at New York University and Columbia University while working as a photographer for the Rockefeller Institute for Medical Research and other research facilities.

After joining the Smithsonian in 1960, he pursued research into the history of photography and published his findings, mainly in technical and scientific periodicals.

Mr. Ostroff, keenly interested in photographic engineering and technology, developed a nondestructive method of restoring faded photographs by neutron activation and consulted with museums and governments around the world on standards for storing and displaying photographs. In 1982, he was invited to inspect the holdings of the Burmese Department of Archaeology in Rangoon, and to advise them on methods to preserve, store and index the items.

He was active in number of professional associations and a recipient of their awards, including the 1989 Society of Photographic Scientists and Engineers' Outstanding National Service Award. He also was a fellow of the Royal Photographic Society.

In retirement, he was working on a book, "What Made Photography Popular? Its Industry and Cultural History," recently submitted for publication.

His marriage to Caroline Lindt ended in divorce.

Survivors include his wife of four years, Elise Ostroff of Washington; three children from his first marriage, Gia Ostroff-Welsh of Jenkintown, Pa., Mika Ostroff-Geiger of Austin and Eric Ostroff of North Hollywood, Calif.; and a sister.