When a mustachioed and smiling man with a large camera dangling around his neck tucked a beer into his jacket pocket and emerged from the gaggle of people surrounding the Bronx Documentary Center, I knew we had arrived at the most happening corner in the Boogie Down on an early Saturday night. The gaggle and the dozens slowly moving around inside the Documentary Center, at the corner of 151st Street and Courtlandt Avenue, were there for the opening night of the new photography exhibit, “Seis Del Sur” (Six From the South [Bronx]), which is garnering loads of positive attention for the artists and the center.