Above from left: “American Gothic, Washington, D.C.,” 1942; “A Choice of Weapons,” 1965; Ethel Shariff in Chicago, 1963.

The late, great Gordon Parks—who died in March 2006 was, among other things, a social activist artist. Setting aside his films—The Learning Tree and Shaft—his poetry, and musical compositions, Parks was a prolific recorder of history. He was pragmatic enough to know, early on, that if he wanted to keep taking photos he had to earn a living at it—and so he got his first chance at learning to “shoot fashions” as he was given to say, by strolling into a white-owned Minneapolis dress shop in 1938, and asking the husband-and-wife owners, the Murphys, if he could have a job photographing the gowns there. Mr. Murphy gave him short shrift, but Mrs. Murphy gave him a job.

That job eventually took him to the Farm Security Administration, where in 1942 he shot American Gothic, Washington, D.C., which he named after Grant Wood’s famous 1930 painting. You have probably seen it. A black cleaning woman stands with a broom in her right hand, and a mop propped against the desk next to her. Behind her hangs the American flag. It’s not an homage to the plain living American, as in Wood’s painting; it was an indictment of segregation and racism in our capital city, something some of the white southern members of the FSA, who didn’t want Parks there in the first place, would have used against him.

“Stryker said you’ve got the right idea, but you’re going to get us all fired,” Mr. Parks said in a telephone interview in Fall 2005. “He put it at the bottom of the pile, but he told me that I should stay with her. He said you had to write cold and hard about black life in America and not allow whites to address the words with the consolation of a few tears.” Parks took it to heart, but wrote his words with images.

Parks stuck with Ella Watson, took photos of her in her apartment with her family, and attending church. She was a person beyond the ironic emblem of African-American as second class citizen. Roy Stryker’s words stuck with Parks, who continued, throughout his life, to capture his fellow blacks in all kinds of situations, from all walks of life.

His work for Life magazine—a chronicle of poverty in Brazil; an exposé of gang violence in Harlem; a chronicle of racial segregation in the deep South; photographic essay on Malcolm X and the Nation of Islam—are moving, stunning, brilliant, memorable, the expert work of a gifted lensman dedicated to exposing and fighting racism, poverty, and injustice.

Gordon Parks: Photographs at His Centennial at the Museum of the African Diaspora (MOAD) in San Francisco celebrates the life of this great American artist with selections from his vast collection that speak of the black experience: An army of Black Muslim women; a portrait of the Fontanelle family from Harlem at the Poverty Board (Welfare Office) in Harlem; Parks wielding his camera in a self-portrait titled “A Choice of Weapons.”

“Untitled, 2008,” by J.D. ‘Okhai Ojeikere

And Ella Watson.

Gordon Parks: Photographs at His Centennial is showing until September 29, 2013. Also showing is J.D. ‘Okhai Ojeikere: Sartorial Moments and the Nearness of Yesterday. Like Parks in America, Ojeikere described, with his camera, rapid political, social, and cultural change of his native Nigeria. The 50 photographs included in this exhibition, dating from 1955 to 2008, capture traditional Nigerian dress and hairstyles alongside popular Western-style interpretations. Hair styles can immediately evoke time and place, fixing the viewer in a country, a town, a society or community, and in an era or year. Ojeikere used hair as an important signifier as he documented the changing body politic of his young nation.