Editing Digital raster graphic

[[File:Topographic map example.png|thumb|300px|A small portion of a USGS DRG]]

A '''digital raster graphic''' ('''DRG''') is a [[digital image]] resulting from scanning a paper [[USGS]] [[topographic map]] for use on a computer.  DRGs created by USGS are typically scanned at 250 [[dpi]] and saved as a [[TIFF]].  The [[Raster graphics|raster]] image usually includes the original border information, referred to as the "map collar".  The map file is [[Universal Transverse Mercator|UTM]] [[map projection|projected]] and [[georeference]]d to the surface of the Earth.  DRG's are regularly used in [[Geographic information system|GIS]] applications. DRGs were first produced in 1995.

==See also==
*[[GeoTIFF]]

==External links==
{{linkfarm|date=November 2016}}
* [[Libre Map Project]] 
** [https://archive.org/details/maps_usgs All 50 States USGS Topographic Maps on the Internet Archive]
** [http://libremap.org USGS Topographic Maps of ALL 50 States]
* [[USGS]] Sites
** [http://topomaps.usgs.gov/drg Digital Raster Graphics] {{Webarchive|url=https://web.archive.org/web/20050521074431/http://topomaps.usgs.gov/drg/ |date=2005-05-21 }}
** [https://web.archive.org/web/20071228110713/http://edcsns17.cr.usgs.gov/EarthExplorer/ Earth Explorer (GeoTIFFs)]
** [https://web.archive.org/web/20130213221700/http://store.usgs.gov/b2c_usgs/usgs/maplocator/%28xcm%3Dr3standardpitrex_prd%26layout%3D6_1_61_48%26uiarea%3D2%26ctype%3DareaDetails%26carea%3D%24ROOT%29/.do Map Locator (GeoPDFs)]
*[http://kymartian.ky.gov/krgmaps/index.html Kentucky Raster Graphics Image Download Center] {{Webarchive|url=https://web.archive.org/web/20060925215612/http://kymartian.ky.gov/krgmaps/index.html |date=2006-09-25 }}
* [http://nris.mt.gov/nsdi/drg.html Montana State Library Digital Raster Graphics download page]
* [[Pennsylvania Spatial Data Access]] sites
** [https://web.archive.org/web/20030802221739/http://www.pasda.psu.edu/access/drg24klist.cgi Digital Raster Graphics for PA (free)]
** [https://web.archive.org/web/20030802221655/http://www.pasda.psu.edu/access/drg24k-clist.cgi Digital raster graphics without collar info for PA (free)]
* [ftp://www.pasda.psu.edu/pub/pasda/other_states/wv/drg24k FTP site, DRGs for West Virginia (free)]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
* [ftp://www.pasda.psu.edu/pub/pasda/other_states/ny/drg24k FTP site, DRGs for New York (free)]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
* [ftp://www.pasda.psu.edu/pub/pasda/other_states/va/drg24k FTP site, DRGs for Virginia (free)]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
* [ftp://www.pasda.psu.edu/pub/pasda/other_states/md/drg24k FTP site, DRGs for Maryland (free)]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
* [ftp://www.pasda.psu.edu/pub/pasda/other_states/dc/drg24k FTP site, DRGs for Washington DC (free)]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
* [ftp://www.pasda.psu.edu/pub/pasda/other_states/de/drg24k FTP site, DRGs for Delaware (free)]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
* [ftp://www.pasda.psu.edu/pub/pasda/other_states/nc/drg24k FTP site, DRGs for North Carolina (free)]{{dead link|date=May 2025|bot=medic}}{{cbignore|bot=medic}}
*[[Texas Natural Resources Information System]]
** [https://web.archive.org/web/20070403201813/http://www.tnris.state.tx.us/digital.htm DRGs without collars organized by county]

[[Category:Cartography]]
[[Category:GIS raster file formats]]
[[Category:United States Geological Survey]]


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