DOQQ

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DOQQ's (Digital Orthographic Quarter-Quads) combine the image characteristics of an aerial photograph  with the geometric qualities of a map. DOQQ's are georeferenced like the other digital map products, but unlike the others, DOQQ's are orthorectified.   Orthophotos are also useful because photos display features that may be omitted or generalized on maps.  These aerial images were taken with 1-meter resolution over the United States.