DRG stands for Digital Raster Graphic, and it is a digital image of a USGS topographic map. The image inside the map neatline is georeferenced 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. Above is an example of a DRG from a small section of a quad in New York.
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