Matt Porterfield says we can credit Jean-Luc Godard's "Masculine-Feminine" (1966) for the interview structure of "Putty Hill." He also says that Martin Bell's hard-to-find "Streetwise," about Seattle street kids, exerted a huge influence on his two films about youth: "'Streetwise' is a documentary that acts like a narrative, 'Putty Hill' is a narrative that acts like a documentary.'"
But he also cited three other masterpieces, readily available on DVD, that are never far from his mind when he thinks of making fiction features with nonfiction techniques.
•Kent McKenzie's "The Exiles" (1961), about American Indians in Los Angeles, uses pungent vignettes, evocative bar music and electric interior monologues to capture how male bonding turns shared weaknesses into an illusion of strength — and to convey the end-of-the-line feelings just beneath the surface of one more round of drinks at a bar.
✭Charles Burnett's "Killer of Sheep" (1977), at its most universal, is about community — what it means to live among kith and kin. At its most particular, it's about what it meant to live in Watts before it devolved from a close-knit section of Los Angeles to the original boyz-'n'-the-hood neighborhood.
•Errol Morris' "Fast, Cheap & Out of Control" (1997). Morris finds the philosophic threads connecting a topiary gardener, a wild-animal tamer, a mole-rat specialist, and a robotics scientist. Porterfield says: "Karen Schmeer, the film's editor, was a big influence on my editor, Mark Vives; it's a documentary, but it takes a strong narrative approach as it weaves together four stories.