Highlights from that collection are now being shown here at Tate Modern. For the next six months (through May 7), “The Radical Eye” presents 191 works from the 1920s to the 1950s by a hit parade of photographers including André Kertesz, Edward Steichen, Man Ray, Irving Penn and Dorothea Lange. (Parts of the collection have been shown at the High Museum of Art in Atlanta in 2000-1 and at the Pinchuk Art Centre in Ukraine in 2007.)