USGS Earth Resources Observation & Science (EROS) Center, 19970514, Digital Orthophoto Quadrangle: DI00000000044769-TETON VILLAGE-NW,WY: U.S. Geological Survey, Menlo Park, CA USA.Online Links:
This is a raster data set. It contains the following raster data types:
The horizontal datum used is North American Datum 1983.
The ellipsoid used is Geodetic Reference System 80.
The semi-major axis of the ellipsoid used is 6378137.
The flattening of the ellipsoid used is 1/297.257.
lta@usgs.gov
DOQs serve a variety of purposes, from interim maps to field references for Earth science investigations and analysis. The DOQ is useful as a layer of a geographic information system and as a tool for revision of digital line graphs and topographic maps.
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Data sources used in this process:
During photographic reproduction of the source photography, limited analog dodging is performed to improve image quality. Analog dodging consists of holding back light from certain areas of the sensitized photographic material to avoid overexposure. The diapositive is inspected to insure clarity and radiometric uniformity. Diapositive image brightness values are collected with a minimum of image quality manipulation. Image brightness values may deviate from brightness values of the original imagery due to image value interpolation during the scanning and rectification processes. Radiometry is verified by visually inspecting the DOQs to the original unrectified image to determine if the DOQ has the same image quality or better image quality than the original unrectified input image. Slight systematic and radiometric differences can be detected between adjacent DOQ files due primarily to differences in source photography capture dates and Sun angles of aerial photography along flight lines. These differences can be observed in an image's general lightness or darkness when compared to adjacent DOQ file coverages.
The DOQ horizontal positional accuracy and the assurance of that accuracy depend, in part, on the accuracy of the data inputs to the rectification process. These inputs consist of the digital elevation model (DEM), aerotriangulation control and methods, the photo source camera calibration, scanner calibration, and aerial photographs that meet National Aerial Photography Program (NAPP) standards. Field control is acquired by third order class 1 or better survey methods sufficiently spaced to meet National Map Accuracy Standards for 1:12,000-scale products. Aerial cameras have current certification from the USGS, National Mapping Division, Optical Science Laboratory. Test calibration scans are performed on all source photography scanners.
The vertical accuracy of the verified USGS format DEM is equivalent to or better than a USGS level-1 or -2 DEM.
All DOQ images are visually inspected for completeness to ensure that no gaps or image misplacement exists in the image area or in overedge coverage. The DOQ images may be derived by mosaicking multiple images, in order to insure complete coverage. All DOQs are cloud free. Some clouds may, very infrequently, be encountered only in the overedge coverage. Source photography is leaf-off in deciduous vegetation regions. Void areas may exist, having a radiometric value of zero and appearing black. These voids are areas for which no photographic source is available or are the result of image transformation from other planimetric systems to the UTM projection. In the latter case, the void sliver areas are on the outside edges of the overedge area. The data set field content of each DOQ header record element is validated to assure completeness prior to archiving in the Sales Data Base.
All DOQ header data and image file sizes are validated by Tape Validation System (TVS) software prior to archiving in the Sales Data Base. This validation procedure assures correct physical format and field values for header record elements. Logical relationships between header record elements are tested.
Are there legal restrictions on access or use of the data?
- Access_Constraints: none
- Use_Constraints:
- None. Acknowledgement of the U.S. Geological Survey is appreciated in products derived from these data.
lta@usgs.gov
Although these data have been processed successfully on a computer system at the USGS, no warranty expressed or implied is made by the USGS regarding the use of the data on any other system, nor does the act of distribution constitute any such warranty.
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Dataset searching and ordering capabilities are available though EarthExplorer at: <http://earthexplorer.usgs.gov>
Delivery Times can be found at: <http://eros.usgs.gov/#/About_Us/Customer_Service/Delivery_Times>
Adequate computer capability is the only technical prerequisite for viewing data in digital form.
lta@usgs.gov