“Life Itself,” the new documentary about Roger Ebert, examines many facets of the nation’s most famous film critic: his newsman background, his exhaustively chronicled battle with cancer that ended in his death last year, his drinking, his wit, his love for his wife, Chaz.

But perhaps one of the most surprising aspects — considering his profession was often reviled by the very people whose work was being examined — is his reputation among filmmakers.

In the film, by Steve James, Ebert is the subject of impressive quotes from directors. “A soldier of cinema,” Werner Herzog says in tribute. “I wouldn’t have a career” without his support, Errol Morris declares. And, in a high compliment from any artist, Martin Scorsese confides, “I didn’t feel inhibited with Roger.”

The critic saw film as a way for people to understand one another and connect, and that devotion extended to his relationships with the filmmakers he championed at crucial points in their careers. Even as he displayed a fearless scrappiness on his television show with Gene Siskel — and published an entire book about movies he hated — Ebert established through his writing a mutual respect with many directors.