Data Layer: DIGITAL ORTHOPHOTO QUADS
You are invited to read the definitions of terms used in this data standard.
||Digital Orthophoto Quads ( DOQ)|
||Digital maps created by the U.S. Geological Survey (USGS). These data are a blend of aerial photography and georeferenced maps. The major source is the National Aerial Photography Program (NAPP), but supplementary data are being used in some parts of the country. Coverage for the United States is not complete; the status for particular areas can be checked on the Internet. Data are in a georeferenced JPEG format, GeoTIFF, or BIL format. The USGS DOQ's come in 3.75-minute blocks, the equivalent of a quarter quad.|
||USGS EROS Data Center|
|Historical Data||For information on past versions of this standard, contact the Chief Data Officer|
Part 270, FW 6, Data Management and Standards, has been superceded by Part 274, FW 2, Establishing Service Data Standards.
Orthophoto Quads - DOQs are available for download from USGS Earth Explorer.
DOQ Fact Sheet - General information on DOQs.
Digital Orthophoto Standards - complete documentation on the DOQs; fairly large, technical document.
||The USGS DOQs are automated to strict standards, and give a very accurate picture of
any given area. They are frequently used as a locational backdrop, but also as a source
for on-screen digitizing. In some parts of the country, DOQs are being produced by
agencies other than the USGS. Any DOQs used by Service personnel should either be obtained
from the USGS or, at a minimum, have been created to meet USGS standards.
The DOQs created by the USGS are all in the UTM projection, NAD83 datum, and can be re-projected like any other georeferenced file.
||Information on the GeoTIFF format, as well as links to a free viewer, can be found at http://earthexplorer.usgs.gov/.|
||March 21, 2000|
||November 29, 2013|
||Chief Data Officer|