U.S. Geological Survey 2000 map Helena, MT Montana State Library https://ftpgeoinfo.msl.mt.gov/Data/Spatial/NonMSDI/Raster/TopoQuads1998/250k/spc/sid https://mslservices.mt.gov/Geographic_Information/Data/DataList/datalist_Details.aspx?did={1C37C4AF-9EF2-42F4-B790-E884CD8285DF} U.S. Geological Survey (USGS) Digital Raster Graphics (DRGs) are scanned raster images of USGS topographic maps. This file contains all the 1:250,000 scale USGS DRGs for Montana, projected to Montana State Plane Coordinates, and merged to form a continuous image in MrSID format. MrSID images can be viewed with free software avaialable at https://www.extensis.com/. The publication dates of the USGS quadrangles whose images were used to create this image may be viewed at https://ftpgeoinfo.msl.mt.gov/Documents/Maps/Individual/20031216_99_q250dates.gif. We received these map images in 1998. The files have not been updated since that time, and many of the maps are more than 50 years old. Newer versions of many of these images may be available for free download at the USGS Store. 1950 1995 Publication Date Complete -116.57 -103.45 49.08 43.76 ISO 19115 Topic Category imageryBaseMapsEarthCover digital raster graphic DRG topographic map Montana Wyoming Idaho None The Montana State Library provides this product/service for informational purposes only. The Library did not produce it for, nor is it suitable for legal, engineering, or surveying purposes. Consumers of this information should review or consult the primary data and information sources to ascertain the viability of the information for their purposes. The Library provides these data in good faith but does not represent or warrant its accuracy, adequacy, or completeness. In no event shall the Library be liable for any incorrect results or analysis; any direct, indirect, special, or consequential damages to any party; or any lost profits arising out of or in connection with the use or the inability to use the data or the services provided. The Library makes these data and services available as a convenience to the public, and for no other purpose. The Library reserves the right to change or revise published data and/or services at any time. Montana State Library mailing address

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Helena Montana 59620-1800 406-444-5354 Montana Relay 711 406-444-0266 geoinfo@mt.gov https://ftpgeoinfo.msl.mt.gov/Documents/Maps/Individual/20031216_99_q250dates.gif https://ftpgeoinfo.msl.mt.gov/Documents/Maps/Individual/20031216_99_q250dates.gif Image showing publication dates of the USGS quadrangles that were used to create the map images. Most DRGs in Montana were produced through and Innovative Partnership agreement between the Land Information Technology Company, Ltd., of Aurora, CO and the USGS. DRGs are faithfully reproduced digital images of the original source maps. Some differences may be detected between the source graphics used and the DRGs due to the RGB values assigned that particular color. The intent is to re-create those colors as near as possible. Data completeness for DRG files reflect content of the source graphics. Features may have been eliminated or generalized on the source graphics due to scale and legibility constraints. For information on collection and inclusion criteria, see U.S. Geological Survey, 1994, Standards for 1:250,000-Scale Digital Line Graphs and Quadrangle Maps: National Mapping Program Technical Instructions and U.S. Geological Survey, 1994, Standards for Digital Line Graphs: National Mapping Program. Approximate horizontal accuracy is 120 meters, assuming source data meets National Map Accuracy Standards. Vertical accuracy is approximately one-half of the mapped contour interval. National Mapping Division U.S. Geological Survey 1950 map Reston, VA U.S. Geological Survey 250000 paper 1950 1996 Publication Date D250 The data set is a mosaic of all the images from this source that are in 1x2 degree quadrangles that intersect Montana. The publication dates of the USGS quadrangles whose images were used to create this image may be viewed at https://ftpgeoinfo.msl.mt.gov/Documents/Maps/Individual/20031216_99_q250dates.gif The production procedures, instrumentation, hardware, and software used in the collection of standard DRG products vary depending on systems used at the contract, cooperator or USGS production sites. The majority of DRG data sets are acquired through government contract. The process step describes, in general, the process used in the production of standard DRG data sets. 1. Production of a DRG begins with the scanning of a paper 120x60-minute topographic map (map1) on a high-resolution scanner. Scanning resolutions range from 500 - 1000 dpi with the output file running between 160-300 mb. 2. Removal of screens (descreening) and color quantization to reduce the number of colors also takes place during the scanning phase. 3. The raw scan file is then transformed and georeferenced using UTM coordinates of the sixteen 2.5-minute grid ticks, which are obtained using the in-house produced program COORDAT and stored in a ground control file. Those sixteen 2.5-minute ticks are interactively visited and assigned their respective UTM coordinates. USGS program XSHAPES4 then performs a piecewise linear rubber sheet transformation. 4. An output resolution of 25.4 meters is chosen in order to resample the file to 250 dpi. 5. The image file is converted to a TIFF and further reduced by converting the file to a run length encoding Packbits compression(type 32773). 6. The color palette of the compressed DRG is then standardized by replacing the original RGB values assigned during the scanning process with standard RGB value combinations using the in-house produced TIFFREMAP program. 7. Prior to archiving the DRG undergoes the following quality assurance procedures: a. The color index values of each DRG are checked to ensure the RGB combinations are consistent with the standardized color palette. b. All DRG files are inspected to ensure that they are geometrically consistent with normal map presentation. c. Selected DRG's are checked to ensure that data elements in the DRG metadata file correspond to the map collar information and to the information in the associated image file. d. Selected DRG's are checked for georeferencing accuracy by comparing the book value of latitude and longitude tick marks with corresponding tick intersections in the DRG image. e. Transformations are checked on selected DRG's by comparing the positions of well defined points, such as UTM grid intersections in the graphic product, with the corresponding image points in the DRG. USGS DRG production specifications are available on request from the National Mapping Division and Mid-Continent Mapping Center by contacting: Rolla-ESIC U.S. Geological Survey 1400 Independence Rd., MS231 Rolla, MO 65401-2602 Phone (573)308-3500 Facsimile (573)308-3615 E-mail to mcmcesic@usgs.gov World Wide Web: http://mcmcweb.er.usgs.gov/drg/ D250 1996 D250B The USGS DRG files were converted to Montana State Plane Coordinates at the Montana State Library using the Arc/Info GRIDWARP command, with 45 control points whose UTM and State Plane coordinates were determined with the Arc/Info PROJECT command. The map collars were then clipped from the files, and the individual images were mosaiced to create a single image with MrSID compression software. D250B 2000 fin Raster Pixel 23704 42753 State Plane Coordinate System 1983 2500 45 49 -109.5 44.25 600000 0 row and column 25.4 25.4 meters North American Datum of 1983 Geodetic Reference System 80 6378137.0 298.257 NGVD29 250 FEET Images of contours Each raster entity or pixel in the original USGS images contained a color index from 0 through 12 referencing a color palette of RGB values from 0 through 255 in which the standard colors used in the DRG are defined. These colors, defined below, have been resampled by the MrSID compression software to form a 24-bit color palette. USGS DRG Color Palette Number Color Red Green Blue 0 Black 0 0 0 1 White 255 255 255 2 Blue 0 151 164 3 Red 203 0 23 4 Brown 131 66 37 5 Green 201 234 157 6 Purple 137 51 128 7 Yellow 255 234 0 8 Light Blue 167 226 226 9 Light Red 255 184 184 10 Light Purple 218 179 214 11 Light Grey 209 209 209 12 Light Brown 207 164 142 Draft Standards for Digital Raster Graphic. Montana State Library mailing address

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Helena MT 59620-1800 406-444-5354 406-444-5354 Montana Relay 711 406-444-0266 geoinfo@mt.gov geoinfo@mt.gov Downloadable Data The Montana State Library provides this product/service for informational purposes only. The Library did not produce it for, nor is it suitable for legal, engineering, or surveying purposes. Consumers of this information should review or consult the primary data and information sources to ascertain the viability of the information for their purposes. The Library provides these data in good faith but does not represent or warrant its accuracy, adequacy, or completeness. In no event shall the Library be liable for any incorrect results or analysis; any direct, indirect, special, or consequential damages to any party; or any lost profits arising out of or in connection with the use or the inability to use the data or the services provided. The Library makes these data and services available as a convenience to the public, and for no other purpose. The Library reserves the right to change or revise published data and/or services at any time. MrSID https://ftpgeoinfo.msl.mt.gov/Data/Spatial/NonMSDI/Raster/TopoQuads1998/250k/spc/sid 20131030 20130417 20040929 20031216 Montana State Library mailing address

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Helena Montana 59620-1800 406-444-5354 Montana Relay 711 406-444-0266 geoinfo@mt.gov FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 {188669BD-21AF-45B6-BD14-DBA38E5CD1C8}