The cause was heart failure, his brother John said.
Mr. Gebhardt was directing the University of Cincinnati Film Society in 1970 when Jonas Mekas, a filmmaker whose work the society had featured, asked him to come to New York and manage Anthology Film Archives, his new center devoted to avant-garde cinema.
Mr. Gebhardt agreed, and soon after he arrived in New York, Lennon and Ms. Ono hired him to work for Joko Films, their production company. Their collaborations over the next three years included “Fly,” which showed, in extreme close-up, a fly (and its many doubles) slowly wandering over a nude woman, and “Up Your Legs Forever,” a series of panning shots of 367 human legs.
“When I was around them, they were one person — two bodies speaking as one person,” Mr. Gebhardt said in an interview with The Cincinnati Enquirer in 2005. He described Lennon as “fantastically smart” and “very open,” adding, “He didn’t have some sneaky hidden agenda.”
In 1972, Mr. Gebhardt filmed the Rolling Stones at four concerts in Fort Worth and Dallas during their “Exile on Main Street” tour, operating one of four cameras, while a sound truck captured the performance in quadraphonic sound, a precursor of surround sound. The resulting film,“Ladies and Gentlemen, the Rolling Stones,” opened in 1974 at large theaters with advanced sound systems, like the Ziegfeld in Manhattan.
Stephen Eric Gebhardt was born on Jan. 6, 1937, in Cincinnati. Both his parents were painters. His father founded the William E. Gebhardt School of Commercial Art, now part of Antonelli College in Cincinnati.
After graduating from high school in 1955, Mr. Gebhardt worked at an architectural engineering firm for three years before enrolling in the University of Cincinnati to study architecture, earning a bachelor’s degree in 1964 and a master’s degree in community planning in 1968.
While at school he became infatuated with film. He founded the film society, began making his own experimental 16-millimeter films and, after leaving school, went to work for Robert Fries Film Productions, a local company that produced mostly commercial work.
He later called on Mr. Fries to join him in New York. The two collaborated at Joko Films, and Mr. Fries did the soundtrack for the Rolling Stones film.
During his stint with Joko Films, Mr. Gebhardt filmed Lennon’s last public concert, a benefit at Madison Square Garden for the Willowbrook State School, an institution for developmentally disabled children. The film, “John Lennon and Yoko Ono Present the One to One Concert,” was broadcast on ABC in 1972. He also made “Gimme Some Truth,” a documentary about the recording of the album “Imagine,” and “Imagine,” a semi-surreal film about a day in the life of Lennon and Ms. Ono.
In 1971 Lennon and Ms. Ono asked him to film a protest concert in Ann Arbor in support of John Sinclair, the manager of the rock group the MC5 and founder of the White Panther Party, who was serving a 10-year prison sentence for giving two marijuana cigarettes to undercover police officers. The concert featured Lennon and Ms. Ono, Phil Ochs, Stevie Wonder, Bob Seger and other performers, as well as a lineup of speakers that included Bobby Seale and Jerry Rubin.
The film, “Ten for Two: The John Sinclair Freedom Rally,” was shown in Britain but not in the United States. Mr. Gebhardt later made a documentary biography of Mr. Sinclair, “Twenty to Life: The Life and Times of John Sinclair” (2004). In the mid-1970s Mr. Gebhardt moved to Los Angeles and worked as an architect. He returned to Cincinnati in 1989 and resumed his film career, winning a grant from the National Endowment for the Arts to make the documentary “Bill Monroe: Father of Bluegrass Music,” broadcast on the TNN network in 1993.
In addition to his brother John, Mr. Gebhardt is survived by another brother, William; a daughter, Elizabeth D’Agostino; and a grandson.
His later work included “Zaha Hadid and the Museum,” a documentary about the Lois and Richard Rosenthal Center for Contemporary Art, which opened in Cincinnati in 2003, and “Italian Postcards,” a series of short films in which a stationary camera simply recorded the ebb and flow of life in Orvieto, Lucca, Florence and Siena.
At his death, he was at work on “Hudson Tigers,” a documentary he began in the mid-1970s about a high school football team in Hudson, Mich., that had won 72 straight games