Matt was born in Rochester, N.Y., and came to Princeton from Benjamin Franklin High School. He joined Prospect Club and majored in the Special Program in the Humanities, writing his thesis on “Samuel Butler: His Conception of the Individual.” He also belonged to the Camera Club. He did graduate work in Near East history and Arabic at the University of Michigan and then spent two years as a teacher at the Friends Boys School in Ramallah, Jordan, before embarking on a lifelong career as a freelance photographer.
Matt and his wife, Jeannine, began working in Mississippi with CORE in 1962, organizing Woolworth pickets, but moved to Jackson in 1963 to work with SNCC. He captured the march from Selma to Montgomery in what he described as “the most intense” moments of his career. His photos of the historic march were published all over the world.
In 1970, Matt and Jeannine sailed their 31-foot sailboat, Aquarius, from New Orleans to West Africa and spent a year cruising down the coast from Mauritania to Ghana. During the 1970s he was sailing master, bridge officer, and photographer on the first two Greenpeace anti-whaling voyages and then served on a North Sea fishing trawler in a successful attempt to stop the Harp Seal hunt. He was arrested by Mounties on the ice and spent six days in jail in the Madeleine Islands.
In retirement, Matt and Jeannine lived in San Rafael, Calif., where he represented photographers of farm labor, played double bass in a community orchestra, and flew his glider on tours of mountains and deserts in California and Nevada.
He is survived by his wife, Jeannine; two children; and five grandchildren.