Robert Arthur Goodnough grew up nearby in Moravia, in the Finger Lakes region.  After earning a fine-arts degree from Syracuse University in 1940 he was drafted into the Army and served in the field artillery, painting portraits and murals at military installations. In 1946 he moved to Manhattan. He studied at the Ozenfant School of Fine Arts and attended Hans Hofmann's celebrated summer school in Provincetown, Mass., where he met the artists Alfred Leslie and Larry Rivers and the critic Clement Greenberg.  At meetings of the Club, a famous downtown discussion group made up mostly of abstract painters, he became friends with Willem de Kooning and Mark Rothko.

Greenberg and the art historian Meyer Schapiro selected him to exhibit in a group show of emerging artists at the Kootz Gallery in 1950, and two years later he had his first important one-man show, at Tibor de Nagy.  He also contributed to Art News, where he wrote "Pollock Paints a Picture," one of the most celebrated of the magazine's artist-at-work articles, with now-legendary photographs of Jackson Pollock in his studio by Hans Namuth.

After earning a master's degree in art education from New York University in 1950, he taught carpentry at the Fieldston School in the Bronx until 1960, when he began making a living from his art. In the early 1970s, Mr. Goodnough began shifting toward Color Field painting, usually executed in acrylic and oil, to which he added his own idiosyncrasies. In Slate Grey Statement, one of the first in this new style, pale dashes of color cluster on a ghostly background of silvery gray. In later paintings the bits of color, now jagged, shardlike and prismatic, take flight across the canvas like a flock of birds. In the 1980s, Mr. Goodnough returned to a style not unlike his earliest work.

Although he never received a retrospective at a major museum, in 1969 Mr. Goodnough was given a one-man show at the Whitney Museum of American Art and the Albright-Knox Art Gallery in Buffalo to showcase his series of serigraph prints One, Two, Three (An Homage to Pablo Casals).

His work is in the following collections: Albright-Knox Art Gallery, Buffalo; Art Institute of Chicago; Baltimore Museum of Art; Birmingham Museum of Art, Alabama; Museum of Modern Art, Whitney Museum of American Art and Metropolitan Museum of Art, New York City; Museum of Fine Arts, Boston; Newark Museum, New Jersey; and the Rhode Island School of Design, Providence.