Urban legends

Boston photographer Peter Urban has captured many celebrities in his lens - Todd English, Keith Lockhart, Mayor Thomas Menino, Fay Wray and designer Carleton Varney (below), Robert B. and Joan Parker, Robert Brustein, and, according to Urban, the "loneliest hotel Christmas tree in Boston." His new exhibit, "Advertising My Friends," is a collection of 16 images based on the premise that "even if all advertising may not be art, all art is advertising." Today's hours are 9 a.m.-6 p.m. (Through Jan. 5; reception Dec. 9 5:30-7 p.m.) Free. Three Columns Gallery, Mather House, Harvard University, 10 Cowperwaite St., Cambridge. 781-424-7018.