The Michael Hoppen Gallery in Chelsea is 20 years old. To mark the occasion, its owner has curated a show called Finders Keepers, dedicated to his own personal collection of photographs - the ones he "has liked and been able to keep", rather than sold. The exhibition and the accompanying catalogue is an illuminating glimpse into the mind of a photographer who became a curator and an obsessive collector. It contains work by the famous -Araki, Avedon, Lartigue - and the lesser-known, as well as several found images by anonymous photographers.