With increasing availability of aircraft and satellite remote-sensor data the working geoscientist now has a new tool at his fingertips. He can gain much from some of these data simply by applying traditional photointerpretive techniques, but still more can be gained if he selectively employs some specialized interpretive techniques. Proper use of the new interpretive techniques requires that the user have a basic understanding of the data he is using-how it is obtained and what it represents. He also must keep in mind the limitations of the data, such as its spectral, spatial, and brightness resolution.

With these considerations in mind, the geoscientist can select the type of remote sensor data that will apply best to his problem and then tailor the processing and analysis of the data to obtain the maximum amount of information with the least expense.

The geoscientist may employ various forms of optical or digital image enhancement or he may choose to use the computer in helping him make his discriminations and classifications. Some enhancement techniques are employed with visual-image analysis, such as color-additive and color-subtractive viewing, stereoscopic and pseudostereoscopic photo interpretation. A few procedures can be accomplished only through computer analysis (brightness ratioing, atmospheric correction), but most are effective with either imagery or digital data. This latter group includes contrast stretching, density slicing, cluster analysis, pattern recognition, frequency analysis, and edge enhancement. Most of these procedures can be done in several ways, with the accuracy of the results and the efficiency of the peration largely dependent on the equipment used. Thus, the economics of the situation are the final consideration in the implementation of most of the more complex interpretive techniques.

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