He likes the way I shake my ass,” a giggling dancer in La Tropical says of director-photographer David Turnley. The Pulitzer- winning photojournalist, who does seem to have a booty fixation, introduces us to the Salon Rosado at La Tropical, a dance hall in a barrio outside of Havana, by training his lens on a succession of gyrating rumps. But Turnley isn’t just an ass ogler; he’s also a historian, if not a particularly talented one. In telling the story of La Tropical, which occupies roughly the same cultural real estate in Cuba as the Apollo Theater does here, he attempts to illuminate the history of race relations in Cuba, with mixed results. The documentary is at its best when it narrows in on a subplot, such as that of star-crossed lovers and dance partners Daivel and Aymé. When Turnley ventures into broader political or sociological commentary, one wishes that he’d step back and let the music, uniformly and ass-shakingly irresistible, take center stage.