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Digital Orthophoto Quadrangles

The Keck Center has approximately 6500 Nevada DOQs which can be identified on the search form provided below. A small number of California, Oregon and Utah DOQs bordering Nevada are also available. All DOQs are geo-referenced, and most are in .tif format with accompanying metadata files (hdr). Some 850 of the DOQs are in USGS native format with metadata included within the file. A DOS applet is available for converting native format DOQs to .tif.

These selected DOQs are provided through the courtesy of the U.S. Bureau of Land Management.

Search for Orthophoto Quads:

DOQname (Quad Name) 
Nevada County (Nevada Counties Only) 

  List all DOQs  (this takes a few moments)

About DOQs

An aerial photograph and an orthophoto or orthoimage may look alike but there are several important differences that allow an orthophoto to be used like a map. A conventional perspective aerial photograph contains image distortions caused by the tilting of the camera and terrain relief (topography). It does not have a uniform scale. You cannot measure distances on an aerial photograph like you can on a map. An aerial photo is not a map. The effects of tilt and relief are removed from the aerial photograph by a mathematical process called rectification. An orthophoto is a uniform-scale image. Since an orthophoto has a uniform scale, it is possible to measure directly on it like other maps. An orthophoto may serve as a base map onto which other map information may be overlaid. The preceding description is from the USGS DOQ page.
 

The mission of the W. M. Keck Earth Sciences and Mining Research Information Center is to provide access for researchers, both on-site and from their remote desktops, to specialized bibliographic databases, scientific visualization and modeling packages, and geospatial data resources.

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Updated 20 April 2008