PHILADELPHIA, PA.- A cornerstone of photographic practice during the late nineteenth and early twentieth centuries, the platinum print is revered by photographers and viewers alike as one of the most beautiful forms of photography, with subtle and lustrous shades that range from the deepest blacks to the most delicate whites. The Philadelphia Museum of Art will present an exhibition of more than 50 works from the late 19th century to the present, showcasing outstanding prints largely drawn from the Museums collection of photographs. The Platinum Process: Photographs from the Nineteenth to the Twenty-First Century , on view February 27 May 23 in the Julien Levy Gallery at the Museums Perelman Building, will include images by early masters of the process including Frederick H. Evans (British, 1853-1943) and Alfred Stieglitz (American, 1864-1946), as well as works by skilled contemporary practitioners such a