Feature films
After returning to civilian life, Graver began his career in Los Angeles working on documentaries for a year before starting to work on larger budget features. Graver wrote and directed his first film, The Embracers, in 1966. He would subsequently serve as the cinematographer and editor on the B-films The Mighty Gorga, The Fabulous Bastard from Chicago, and Satan's Sadists (all 1969).
In 1970, Graver made an unannounced inquiry to Orson Welles, saying he wanted to work with the director. Welles told Graver that only one other person had ever called him to say they wanted to work with him—Gregg Toland, who had worked with Welles on Citizen Kane. Journalist Josh Karp reported:
From that day forward, Orson Welles was the central figure in Gary Graver's life: more important than his wife, his children, his bank account, and his health. For the rest of Orson's life (and his own) Graver belonged to the great director."
Welles and Graver started work on the unfinished film The Other Side of the Wind, in addition to other projects Welles had in the works including F for Fake (1973), which Graver co-shot with French cinematographer François Reichenbach; and Filming Othello (1978).
Graver's work for Welles was unpaid, and during the shooting of one scene in The Other Side of the Wind, Welles used as a prop his 1941 Oscar that he won as the co-writer of Citizen Kane. When shooting was finished, he handed the statuette to Graver saying, "Here, keep this." Graver understood this to be a gift in lieu of payment for his work. Graver held onto the award for several years until he ran into financial trouble in the 1990s, and in 1994 he sold it for $50,000. The purchaser, a company called Bay Holdings, then attempted to sell it at auction through Sotheby's in London. When Welles's daughter Beatrice Welles learned of the intended sale, she successfully sued both Graver and the holding company to stop it. She eventually took possession of the statuette before attempting to sell it herself, however Christie's withdrew it from auction after the Academy objected to the sale.
Besides his work with Welles, Graver also worked for other Hollywood directors including Roger Corman and Fred Olen Ray. The bulk of his output was B-movies since, as he put it, "I knew how to make a movie without much money." While working on The Other Side of the Wind between 1970 and 1976, Graver worked as a cinematographer and editor in various other B-horror films such as Blood Mania (1970), Dracula vs. Frankenstein (1971), and Invasion of the Bee Girls (1973). The following year, Graver contributed additional camerawork on John Cassavetes's A Woman Under the Influence (1974). In 1977, he served as cinematographer for Ron Howard's Grand Theft Auto, followed by the cult horror film The Toolbox Murders (1978).
In 1982, Graver wrote, directed, edited, and produced the slasher film Trick or Treats, after which he served as cinematographer on the slasher film Mortuary (1983), and the comedy Chattanooga Choo Choo (1984). He directed the thriller film Moon in Scorpio starring Britt Ekland in 1987, followed by a cinematography credit on Twisted Nightmare (1988). The following year, Graver provided additional cinematography on Steven Spielberg's Always (1989), working on the film's Montana unit.