Plate 1

Blue (450-480 nm)

Green (530-560 nm)

Red (625-675 nm)

     Colour composite         Key   Habitat/object type

Figure 1.2 Hypothetical images of a small imaginary atoll in the Indian Ocean recorded by a sensor measuring the amount of sunlight reflected in the blue, green and red parts of the visible spectrum. The upper three images show hoe each sensor waveband records the different habitats/objects. The colour composite image at the bottom is created by displaying the blue band image on the computer monitor's blue gun, the green band image on the green gun, and red band image on the red gun. Because the sensor is recording at wavelengths similar to those used in human vision, the colour image is similar to what we would see if we flew over the atoll. The inset area is discussed further in Figure 1.3 (Plate 2).