'Columbus' muses on modernism, David Hockney turns 80

The Los Angeles-based painter David Hockney turned 80 last month and his birthday is being marked with shows from London to LA's Getty Museum. Critics and Hockney talk to DnA about his enduring appeal. And the movie Columbus is set in the small town of Columbus, Ind., a mecca of modernist architecture. The filmmaker, Kogonada, explains why he placed buildings at the center of his directorial debut.