Exposure - the deceptively simple concept at the very heart of photography - has always been a subject of fascination to aspiring amateurs and professional photographers alike. Recent developments in digital technology have transformed the ways in which exposures can be manipulated, and this in turn has forced photographers to think about what they can acheive by understanding the variables of aperture, ISO and time. Michael Freeman takes the reader through this difficult and fast-moving area with a lucid and accesible method, using histograms and clear, visual examples to explore the subtleties of the subject and enable the reader to shoot with confidence.