Julia Margaret Cameron (1815-79) was one of the most important and innovative photographers of the 19th century. Criticised in her lifetime for her unconventional techniques, she is now celebrated as a pioneering portraitist. 2015 marks the bicentenary of Cameron's birth and the 150th anniversary of her first museum exhibition - the only one in her lifetime - held at the Victoria and Albert Museum in 1865. Drawing on the V&A's significant collection, which includes photographs acquired directly from Cameron and letters she wrote to the museum's founding director, Curator Marta Weiss tells the story of Cameron's artistic development. She also presents, for the first time, a group of photographs recently revealed to have belonged to Cameron's friend and mentor the artist G.F. Watts. This discovery sheds light on previously unacknowledged aspects of Cameron's experimental approach.