The application of reflected infrared color film to the study of environmental problems

The technique of color infrared photography in the near, or reflected, infrared range is explained and its several applications to the remote sensing of environmental problems are presented. The development of infrared photography is traced from the discovery of infrared radiation by Herschel in 1800, considering the development of photographic media from colloidion emulsions to present-day cyanine dyes. The properties of three-layer color infrared, or false-color, film are examined, and the problems of the instability of infrared dyes and the color balance of color infrared photography are considered. Finally, applications of color infrared photography to the study of the health of farm crops, forests and grazing lands, the estimation of crop yields and the determination of land/water interfaces, water quality and flood plains are discussed.