Lategan was born in South Africa in 1935 and came to England to study at the Bristol Old Vic Theatre School. His study was interrupted by a call to National Service in Germany, where he developed an interest in photography. After returning to South Africa, he trained with photographer Ginger Odes in Cape Town. He returned to London in the early 1960s to open a photographic studio. He is best known for discovering Twiggy and producing iconic images of the British model.
After living in the US throughout the 80s, Lategan now resides and continues to work in London. His photographs have been exhibited and retained by the Victoria and Albert Museum, The National Portrait Gallery, the Olympus Gallery, the Royal Photographic Society, Bath, and the South African National Gallery.