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Resolution: sensor characteristic that affect what can be seen in an image Source: NASA Spatial resolution Spectral characteristics Temporal characteristics Sensor sensitivity SPATIAL RESOLUTION Spatial resolution refers to the amount of detail that can be detected by a sensor. It is the smallest unit measured; Images where only large features are visible are said to have coarse or low resolution. In fine or high-resolution images, small objects can be detected. Detailed mapping of land-use practices requires a much greater spatial resolution. Size of an image pixel in ground dimensions. Usually represented by the length of one side of a square (i.e., 30m resolution). The spatial resolution of passive sensors depends primarily on their Instantaneous Field of View (IFOV). The IFOV is the angular cone of visibility of the sensor (A) and determines the area on the Earth’s surface which is “seen” from a given altitude at one particular momen

Electromagnetic Spectrum EMR is a form of energy exhibiting wave-like behaviour as it travels through space. EMR ranges from very high energy radiation such as gamma rays and X rays through ultraviolet light, visible light, infrared radiation and microwaves to radio waves.  The range of frequencies of EMR is known as the electromagnetic spectrum. The Sun produces a continuous spectrum of energy from gamma rays to radio waves that continually bathe the Earth in energy. The visible portion of the spectrum may be measured using wavelength (measured in mm or nm) or electron volts (eV) - All units are interchangeable. Classification of Electromagnetic Radiation Infrared radiation (750 nm - 1 mm) The infrared region can be divided into two categories based on their radiation properties - the reflected IR, and the emitted or thermal IR. The reflected IR covers wavelengths from approximately 0.7 micrometres to 3.0 micrometres. The thermal IR covers wavelengths from approxima