A respected photographer, writer, and composer, Gordon Parks hardly seems like the guy to inaugurate the genre that became known as “blaxploitation.” But Parks’s Shaft (pictured) and Shaft’s Big Score! did indeed launch the ’70s African-American update of the tough-guy flick, with a little help from Isaac Hayes’ theme song. As seen in this retrospective, Parks’ short Hollywood career began and ended with very different sorts of films: 1969’s The Learning Tree (shown with Moments Without Proper Names, Oct. 26 at 4 p.m.) was adapted from his own autobiographical novel about growing up in small-town Kansas in the ’20s, while 1976’s Leadbelly (Oct. 13 at 2:30 p.m.) is a lyrical but tough-minded account of the singer who wrote such classics as “Bourgeois Blues” and “Goodnight Irene.” Most of the other works in this series, which is presented in association with the Corcoran Gallery’s exhibit of Parks’ÿ20work, were made for television. They include Solomon Northrup’s Odyssey, the true story of a free black musician who was kidnapped on a visit to Washington and sold into slavery, and Martin, Parks’ film of his own ballet about the life of Martin Luther King Jr. (shown together, Oct. 18 at 2:30 p.m.). Shaft and Shaft’s Big Score! will be shown together this Sunday at 4 p.m., and Parks will appear to introduce the Oct. 26 program. At the National Gallery of Art’s East Building Auditorium, 4th & Constitution Ave. NW. FREE. (202) 737-4215. (Mark Jenkins).