Denner graduated from the University of Cardiff with a BSc & PhD in biochemistry. After four years academic research he joined the Food Science Division of the Ministry of Agriculture, Fisheries & Food in London in 1972 & lived in Upminster, Essex. In 1992 he was appointed Chief Scientist (Food).

During the whole of this period he was a very keen amateur photographer & developed an aptitude for ‘street photography’. He lectured to Photographic Societies & judged competitions including International Salons of Photography. In 1996 his passion for photography got the better of him & he took early retirement from the Civil Service to become a professional photographer. Since that time he has been a press photographer specializing in live music, especially rock, blues, jazz & world music. He worked successfully with Retna Picture Agency (now part of Photoshot) & his photographs have been published in newspapers & magazines worldwide.

In 2013 he retired from live music photography & moved to High Kelling in Norfolk to work on his photographic archive.