Interpreting satellite imagery

There are limits to a person's ability to distinguish small differences in color. We are especially limited in our resolution of shades of gray. If data are collected using 256 shades of gray, but an analyst can only distinguish 8-10 (optimistically) of them, a great deal of information is potentially lost. The human interpreter is outpaced by the precision of the data. Computers, however, have no trouble distinguishing 256 shades of gray. Each one is individually recognizable. In addition, the analyst has control over the computer's presentation of the data. She can group it any way she pleases, extract a portion of it, or display it in false color. Data sets can also be combined, compared, and contrasted with more ease and precision (not to mention speed) than if the task was left to humans alone. In order to know what is what in an image, the analyst may use an algorithm.

Human interpretations are highly subjective, hence, not perfectly repeatable. Conversely, results generated by computer -even when erroneous- are usually repeatable.

When very large amounts of data are involved (a series of photos of an apple grove taken at 5 day intervals over an entire growing season) the computer may be better suited to managing the large body of detailed (and tedious) data.