Ground level reflectance measurement techniques - An evaluation with emphasis on the importance of spectral calibration

The bandpasses, overflight conditions, and sensor geometry that will provide optimum target discrimination in remote-sensing studies can be determined only from spectral reflectance measurements made for various sun-target-sensor geometries, supplemented by model calculations which can be checked against field data. The accurate measurement of ground reflectance properties is critical to the design of future sensors and to the determination of imaging conditions. The current investigation has the objective to review typical methods of measuring spectral reflectance, to point out some of the problems inherent to reflectance measuring techniques, and to present a method of checking measurement accuracy.