Preface Acknowledgements Author biography Part I Energy and photography 1 The nature of energy 1.1 Energy transfer 2 Energy and exposure 2.1 Defining our terms 2.1.1 Power, P 2.1.2 Intensity, B 2.1.3 llluminance, I 2.1.4 Specific intensity, I0 2.2 Tracing the energy from source to camera 2.2.1 The power of light emitted by the Sun 2.2.2 The intensity of sunlight at Earth 2.2.3 Illuminance of the light on the subject 2.2.4 The power of the light intercepted by the metal disk 2.2.5 The power of the light reflected by the metal disk 2.2.6 The intensity of the reflected light when it reaches the camera 2.2.7 The power of the light that enters the camera lens 2.2.8 The illuminance of the light on the camera detector 2.2.9 The exposure imparted to the detector 2.2.10 Summary of steps 2.3 The Jones-Condit equation Reference 3 Shutter speed and aperture 3.1 Power and shutter speed 3.2 Aperture and focal ratio 3.2.1 The effect of focus on exposure 4 Density and the elements of exposure 4.1 Reciprocity and exposure 4.2 Camera settings 4.3 Choosing between equivalent settings 4.3.1 Aperture and depth of focus 4.3.2 Shutter speed and motion blur 4.3.3 ISO and noise 4.3.4 Changing the light 4.3.5 Navigating the trade-offs 4.4 Exposure value (EV) References 5 Metering 5.1 Direct-read versus meters 5.2 Reflected-light metering 5.2.1 Spot, center-weighted and matrix metering 5.2.2 Manual, automatic, semi-automatic and program exposure modes 5.3 Incident-light metering 5.4 Flash 5.4.1 Distance and flash 5.4.2 Flash metering 5.4.3 Fill flash