What is a Digital Raster Graphic?A digital raster graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Universal Transverse Mercator projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The map is scanned at a minimum resolution of 250 dots per inch.
How to Obtain DRGsFrom USGS Business PartnersThe USGS has private-sector business partners who sell USGS maps and digital data. Buying from these companies is usually the fastest way to obtain USGS products.
From USGS Data PartnersThe USGS does not make or sell DRGs for the following areas because of cooperative agreements with other agencies. See the DRG status graphic for approximate areas of coverage. The technical specifications for DRGs from these sources differ slightly from USGS specifications.
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