Most all early aerial photographs were only taken in black and white. However, these types of photos are limited in their usefullness to analyze specific data about an environment because it can only depict shades of gray between black and white. Areas in the photograph with certain similar light wavelengths will appear muddled together. There are still uses in modern technology for black and white filters when using infrared imaging and other devices. These filters block out certain undesired wavelengths according to the required specifications. This photograph (1950) shows downtown Johnstown, Pennsylvania. It represents a series of photographs which show its rebuilding after a flood in 1889. You can see the artificial embankments used to protect the downtown area from future flooding of the river.
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