SHARON, Conn. — Robert Drew, a pioneer of the modern documentary who in “Primary” and other movies mastered the intimate, spontaneous style known as cinema verite and schooled a generation of influential directors that included D.A. Pennebaker and Albert Maysles, has died at age 90.

His son Thatcher Drew confirmed he died Wednesday morning at his home in Sharon.

Starting in 1960 with “Primary,” Drew produced and sometimes directed a series of television documentaries that took advantage of such innovations as light, hand-held cameras that recorded both sound and pictures.

With filmmakers newly unburdened, nonfiction movies no longer had to be carefully staged and awkwardly narrated. Directors could work more like journalists, following their subjects for hours and days at a time and capturing revealing moments. Little, if any, voiceover was needed.

Drew’s dozens of films included “The Chair,” a 1963 documentary about a death penalty case in Illinois, and “784 Days That Changed America: From Watergate to Resignation,” winner in 1982 of a Peabody award.

Many of his movies were edited and co-produced by his wife, Anne Drew, who died in 2012.