drgclip

Citation:

Citation Information:

Originator: U.S. Geological Survey (USGS), Maine Office of Geographic Information Systems (MEGIS) (comp.)(ed.)
Publication Date: 19991231
Title: drgclip
Geospatial Data Presentation Form: raster digital data
Series Information:

Series Name: Maine GIS
Issue Identification: SDE server; Internet Data Catalog

Publication Information:

Publication Place: Augusta ME
Publisher: Maine Office of Geographic Information Systems

Other Citation Details:
1:24000 Maine Office of Geographic Information Systems (MEGIS) has developed a set of collarless DRGs. The process applied by MEGIS is described in FGDC metadata for DRGCLIP. Publication date is unique to each quadrangle in the map series, additional information on the source dates of USGS DRGs used to develop DRGCLIPs for Maine can be found in .dbf and comma delimited text format at http://megis.maine.gov/catalog/ "Tables" link. For additional information contact MEGIS at 1-207-287-6144.

Online Linkage: http://megis.maine.gov/catalog/

Description:

Abstract:
DRGCLIPs are collarless digital raster graphics (DRGs), produced from 1:24,000 USGS DRGs covering all of Maine. These are .TIFF format images of US Geological Survey (USGS) 7.5 minute series topographic maps, clipped from USGS Digital Raster Graphics (DRGs) for Maine. DRGCLIPs do not include map collar information. Each image represents the area, of a USGS DRG, inside the map neatline and is georeferenced to the surface of the Earth. DRGCLIPs retain, from the USGS DRG source, the associated .tfw files and the GeoTIFF 0.2 specifications that define a set of TIFF tags. The tags describe all cartographic information associated with the source file. This GeoTIFF information now contains the UTM projection and the NAD83 datum. DRGCLIPs retain the 8-bit color image of the USGS DRGs. USGS DRGs employ a standardized color palette to ensure uniform colors throughout.
Purpose:
DRGs can be used to collect, review, and revise other digital data. When the DRG is combined with other digital products, such as digital orthophoto quadrangles (DOQ) or digital elevation models (DEM), the resulting image provides additional visual information for the extraction and revision of base cartographic information. It can also be used to produce "hybrid" products. These include combined DRGs and DOQs for revising and collecting digital data, DRGs and DEMs for creating shaded-relief DRGs, and combinations of DRG, DOQ, and DLG data. Although a standard DRG is an effective mapping tool, its full potential for digital production is realized in combination with other digital data.
Time Period of Content:

Time Period Information:

Range of Dates/Times:

Beginning Date: 1/1/1948
Beginning Time: Unknown
Ending Date: 12/31/1995
Ending Time: Unknown

Currentness Reference: source dates

Status:

Progress: Complete
Maintenance and Update Frequency: As needed

Spatial Domain:

Bounding Coordinates:

West Bounding Coordinate: -71.3
East Bounding Coordinate: -66.8
North Bounding Coordinate: 47.6
South Bounding Coordinate: 42.9

Keywords:

Theme:

Theme Keyword Thesaurus: Maine GIS Thesaurus-Theme
Theme Keyword: digital raster graphics
Theme Keyword: topographic map images

Theme:

Theme Keyword Thesaurus: ISO Keyword Thesaurus
Theme Keyword: imageryBaseMapsEarthCover

Place:

Place Keyword Thesaurus: Maine GIS Thesaurus-Place
Place Keyword: Maine
Place Keyword: Gulf of Maine
Place Keyword: United States

Stratum:

Stratum Keyword Thesaurus: GCMD Parameter Keyword
Stratum Keyword: human dimensions

Access Constraints:
Secondary distribution by permission only. Please see Maine Office of Geographic Information Systems (MEGIS) License Agreement at http://megis.maine.gov/ . Any secondary distribution must have this documentation appended.
Use Constraints:
Users must assume responsibility in determining the usability of this data for their purposes. Digital maps retain the accuracy of their source materials. The best use of data mapped at scales of 1:500,000 and 1:250,000 is in statewide planning and studies; at 1:100,000 in regional planning and studies; at 1:62,500 and 1:24,000 in detailed studies and local planning; and at 1:12,000 and 1:5,000 or larger scales in parcel level studies and detailed local planning. In the use of Maine GIS data, please check sources, scale, accuracy, currentness and other available information. Please confirm that you are using the correct copy of both data and metadata from the Maine GIS Data Catalog. The Maine Office of Geographic Information Systems (MEGIS) provides notice of updates and corrections directly to the Maine GIS Technical Group and Maine GIS Users, through the MEGISTECH and MEGISUSER list servers. To subscribe please contact MeGIS through the Maine Office of Information Technology (OIT) Customer Support Center (CSC) at (207) 624-7700. To request data correction in, or provide updates to Maine GIS data, please use the contact information contained in the metadata. Updates, corrections, and feedback, incorporated in the Maine GIS database are made in accordance with "Data Standards for Maine Geographic Information Systems", 2002, and coordinated by MEGIS in consultation with the Maine GIS Executive Council.
Point of Contact:

Contact Information:

Contact Organization Primary:

Contact Organization: (MEGIS) Maine Office of Geographic Information Systems

Contact Position: GIS Coordinator
Contact Address:

Address Type: mailing address
Address: State House Station 145
City: Augusta
State or Province: ME
Postal Code: 04333-0145
Country: USA

Contact Voice Telephone: (207) 624-7700
Contact Facsimile Telephone: (207) 287-3842
Hours of Service: Monday through Friday 0800 - 1700 EST

Data Set Credit: Credit should always be given to the data source and/or originator when the data is transferred or printed.
Native Data Set Environment:
Maine Office of Information Technology (OIT) Oracle 9i, Maine Office of Geographic Information Systems (MEGIS), Maine GIS SDE, SDEUSER, SDE.DEFAULT, Maine GIS Internet Data Catalog http://megis.maine.gov/catalog/, Maine GIS ArcIMS http://megisims.state.me.us/website/basemap/viewer.htm, Maine GIS server ArcInfo version 9, Solaris 9, pathname = /home23/drgs/24k/<tile_name>/drgclip, file size ~6.5 MB
Cross Reference:

Citation Information:

Originator: U.S. Geological Survey (USGS)
Publication Date: 20000901
Title: DRGMETA
Geospatial Data Presentation Form: tabular digital data
Series Information:

Series Name: Maine GIS
Issue Identification: SDE server; Internet Data Catalog; Tables

Publication Information:

Publication Place: Augusta ME
Publisher: Maine Office of Geographic Information Systems (MEGIS)

Online Linkage: http://megis.maine.gov/catalog/

Attribute Accuracy:

Attribute Accuracy Report:
The source of this DRGCLIP, the USGS DRG. USGS DRGs are examined to ensure color consistency within a series. Inspections are performed on selected DRGs to ensure that both the order of digital numbers and digital number values are correct. Colors will be checked for color compliance to map series and for major color differences between features on the DRG and similar features on the source map. Color consistency throughout each series is checked by comparing a DRG to its neighboring quadrangles whenever possible.
Logical Consistency Report:
The USGS DRG is produced with the intention of replicating as close as possible the original source map. Users will note, however, that a certain amount of "noise" can be discerned when small areas are blown up or viewed under zoomed-in conditions. This noise is in the form of random specks or pixels of color and halos due to any number of factors, such as, the quality of the source, the use of screens and patterns on the litho, and the unevenness of ink due to saturation and absorption. Discontinuities or breaks in linear features may also be present and are due to improper calibration or usage of the scanner, the condition of the source, and resampling. Descreening, quantizing, and noise filtering are methods used to reduce noise, which, besides creating a more aesthetically pleasing image, have the added benefit of reducing the size of the image file. Removal of lithographic screen patterns is preferred but not required.
Completeness Report:
The USGS has checked for image completeness by visually inspecting a sampling of DRGs. Each was examined for gaps (missing data) in the main body of the map, the map collar, the overedge areas, and any insets. The map collar and all its contents have been removed from DRGCLIPs for Maine.
Positional Accuracy:

Horizontal Positional Accuracy:

Horizontal Positional Accuracy Report:
USGS DRGs have been accuracy tested. The accuracy test was performed by comparing the positions of UTM grid intersections on the source graphic against the corresponding location on the digital image. A visual inspection will determine whether those coordinates fall within the pixels that define a grid tick. USGS DRGs duplicate the horizontal accuracy of the source maps.
Quantitative Horizontal Positional Accuracy Assessment:

Horizontal Positional Accuracy Value: 12
Horizontal Positional Accuracy Explanation:
USGS DRGs retain the horizontal accuracy of the source maps. Most USGS printed maps contain the National Map Accuracy Standards (NMAS) note in the collar area. The NMAS states that for maps on publication scales of 1:20,000 or smaller, not more than 10 percent of the points tested shall be in error by more than 1/50 inch measured on the publication scale. Test points must be "well-defined", that is, easily visible or recoverable on the ground. For DRGs this accuracy statement applies only to that area of the DRG that falls within the neatline of the source map (excluding inset areas). Overedge areas falling outside the transformation boundary area (the map neatline), can exhibit anomalies or discrepancies. These anomalies also appear in the map inset areas and in the map collar. For maps without the NMAS note, the horizontal accuracy is unknown. The DRGCLIPs retain the accuracy of the source map. The map collar and all its contents have been removed from DRGCLIPs for Maine.
Vertical Positional Accuracy:

Vertical Positional Accuracy Report:
National Geodetic Vertical Datum of 1929. USGS topographic maps utilize the vertical positional accuracy of the source. This accuracy is retained in USGS DRGs; however, the DRGCLIPs for Maine have been projected to NAD83 and vertical positional accuracy of elevation data may be affected by this conversion. The National Map Accuracy Standard applies to USGS topographic maps. At all map scales, the maximum allowable vertical tolerance is one half the published contour interval.
Lineage:

Source Information:

Source Citation:

Citation Information:

Originator: U.S. Geological Survey (USGS)
Publication Date: 199804
Publication Time: Unknown
Title: (DRG) Digital Raster Graphics
Edition: 1.0
Geospatial Data Presentation Form: raster digital data
Series Information:

Series Name: USGS Digital Raster Graphics
Issue Identification: Digital Raster Graphics (DRGs) are scanned color images of USGS topographic maps

Publication Information:

Publication Place: Sioux Falls
Publisher: U.S. Geological Survey

Other Citation Details:
Earth Science Information Centers (ESIC) offer nationwide information and sales service for USGS map products and earth science publications. Additional metadata on USGS DRGs for Maine can be found in .dbf and comma delimited text format at http://megis.maine.gov/catalog/ tables link. For additional information, contact any USGS Earth Science Information Center (ESIC), or call 1-800-USA-MAPS.
Online Linkage: http://edcwww.cr.usgs.gov

Source Scale Denominator: 24000
Type of Source Media: CD-ROM
Source Time Period of Content:

Time Period Information:

Range of Dates/Times:

Beginning Date: 1/1/1948
Beginning Time: Unknown
Ending Date: 12/31/1995
Ending Time: Unknown

Source Currentness Reference: ground condition

Source Citation Abbreviation: drg
Source Contribution: The collar information was removed from USGS Digital Raster Graphic (DRGs) to create DRGCLIP images for Maine GIS.

Process Step:

Process Description:
Originally clipped DRGs were created from standard USGS 1:24000 Digital Raster Graphics (DRGs) for use by the Maine Forest Service, as part of an Arcview application. USGS DRGs contain the white margin and legend areas found on paper USGS quadrangles. This is inconvenient for those operations needing to mosaic several adjacent quads, so the following procedure was established. The Maine Forest Service has statewide jurisdiction, the project area covered the entire state of Maine. MFS has nine ranger districts, and the finished clipped DRG products were grouped onto CDs corresponding to those districts. The work environment was established in the following steps. The base data was 1:24000 scale USGS DRG quads on CD, supplied by USGS EROS data center, dated April 1998. The DRGs were in a UTM NAD27 georeferenced TIFF format. The data was supplied on CDs conforming to 1:250000-scale tile structure. Each tile was identified by alphanumeric format, not by tile name. In order to conform to MEGIS tile structure, and for operator convenience, the finished products would need to have the appropriate quadrangle names. Each USGS-supplied CD had a text file containing the DRG identification code and the corresponding quad name. For each CD, this data was imported to a Microsoft Access file, edited, then exported to an Info file called Quad.dat. The purpose of this Info file was to select the appropriate TIFF file for each tile when processing, and to name the output file by its quadrangle names. DRGs were processed in batches corresponding to MFS districts. An Arc/Info coverage was created which represents the MFS ranger districts. The getdist.aml was used to establish a workspace for a given district. The AML then created a polygon coverage of the district boundaries by reselecting from the MFS district coverage.
Source Used Citation Abbreviation: drg
Process Date: 199910
Process Contact:

Contact Information:

Contact Organization Primary:

Contact Organization: (MEGIS) Maine Office of Geographic Information Systems

Contact Position: GIS Coordinator
Contact Address:

Address Type: mailing address
Address: State House Station 145
City: Augusta
State or Province: ME
Postal Code: 04333-0145
Country: USA

Contact Voice Telephone: (207) 624-7700
Contact Facsimile Telephone: (207) 287-3842
Hours of Service: Monday through Friday 0800 - 1700 EST

Process Step:

Process Description:
In October 2000, The Maine Department of Environmental Protection used the following process to create clipped DRGs projected to NAD83 and these were used to replace and upgrade original DRGCLIPS at MEGIS. All processes were completed using ArcInfo and ArcInfo GRID. The DRG TIFF image was converted into an ArcInfo GRID using the "imagegrid" command. To remove the collars from the DRG, the DRG grid was then clipped to the extent of the quadrangle using the MEGIS 7.5 minute map series index, 24KINDEX. The collarless, DRG grids were then projected from NAD27 to NAD83 using the ArcInfo "project" command with the "grid" option. The DRG grids were buffered by 100 meters and edges of adjacent grids were merged to fill in the "null" values providing data to complete "tiles" , and finally grids were converted back to TIFF images using the ArcInfo "gridimage" command.
Source Used Citation Abbreviation: drg
Process Date: 200010
Process Contact:

Contact Information:

Contact Organization Primary:

Contact Organization: (MEGIS) Maine Office of Geographic Information Systems

Contact Position: GIS Coordinator
Contact Address:

Address Type: mailing address
Address: State House Station 145
City: Augusta
State or Province: ME
Postal Code: 04333-0145
Country: USA

Contact Voice Telephone: (207) 624-7700
Contact Facsimile Telephone: (207) 287-3842
Hours of Service: Monday through Friday 0800 - 1700 EST

Cloud Cover: 0

Indirect Spatial Reference: 751 image mosaic of Maine
Direct Spatial Reference Method: Raster
Raster Object Information:

Raster Object Type: Pixel
Row Count: 204495
Column Count: 138708

Horizontal Coordinate System Definition:

Planar:

Grid Coordinate System:

Grid Coordinate System Name: Universal Transverse Mercator 1983
Universal Transverse Mercator:

UTM Zone Number: 19
Transverse Mercator:

Scale Factor at Central Meridian: 0.9996
Longitude of Central Meridian: -69
Latitude of Projection Origin: 0
False Easting: 500000
False Northing: 0

Planar Coordinate Information:

Planar Coordinate Encoding Method: Row and Column
Coordinate Representation:

Abscissa Resolution: 1
Ordinate Resolution: 1

Planar Distance Units: meters

Geodetic Model:

Horizontal Datum Name: North American Datum of 1983
Ellipsoid Name: Geodetic Reference System 80
Semi-major Axis: 6378137
Denominator of Flattening Ratio: 298.257

Overview Description:

Entity and Attribute Overview:
Each DRGCLIP is a raster image. Pixels contain a digital number 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.

Entity and Attribute Detail Citation: USGS Digital Raster Graphic Standards

Distributor:

Contact Information:

Contact Organization Primary:

Contact Organization: (MEGIS) Maine Office of Geographic Information Systems

Contact Position: GIS Coordinator
Contact Address:

Address Type: mailing address
Address: State House Station 145
City: Augusta
State or Province: ME
Postal Code: 04333-0145
Country: USA

Contact Voice Telephone: (207) 624-7700
Contact Facsimile Telephone: (207) 287-3842
Hours of Service: Monday through Friday 0800 - 1700 EST

Distribution Liability:
Users must assume responsibility to determine the usability of this data for their purposes. Although these data have been processed successfully on a computer system at the Maine Office of Geographic Information Systems, no warranty expressed or implied is made by MEGIS regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. Neither the Maine Office of Geographic Information Systems, nor any of its contributors, is liable for misuse of the data, for damage, for transmission of viruses, or for computer contamination through the distribution of these data sets.
Standard Order Process:

Digital Form:

Digital Transfer Information:

Format Name: GeoTIFF
Format Specification: Tagged Image File Format
Format Information Content:
TIFF image format is in widespread use in the desktop publishing world. It serves as an interface to several scanners and graphic arts packages. TIFF supports black-and-white, grayscale, pseudo color, and true color images, all of which can be stored in a compressed or decompressed format. TIFF images may contain georeferencing information in header tags, or a .tfw file, defined by the GeoTIFF standard. ArcGIS currently supports GeoTIFF tags.
File Decompression Technique:
Data available from this website is in .zip compressed format. WinZip is a Windows based, PKZip-compatible compression utility. You will need a program like this to extract the data. A link to a trial copy WinZip software is available at http://megis.maine.gov/links/.
Digital Transfer Option:

Online Option:

Computer Contact Information:

Network Address:

Network Resource Name: http://megis.maine.gov/catalog/

Access Instructions:
These data are available to Internet browsers for download from the Maine GIS Internet Data Catalog. Data available from this website is in .zip compressed format. WinZip is a Windows based, PKZip-compatible compression utility. You will need a program like this to extract the data. A link to a trial copy WinZip software is available at http://megis.maine.gov/software.asp. If you are not already a GIS user, free software for viewing these files is available from Environmental Systems Research Institute, Inc. (ESRI). See http://megis.maine.gov/links/ for a link to ArcExplorer 9.x .
Digital Transfer Option:

Online Option:

Access Instructions: Where file size and Internet access permit, data requests can be made available via File Transfer Protocol (FTP).

Fees: Data may be downloaded from Maine GIS Internet Data Catalog at no charge.
Turnaround: Data is available for immediate download from the Maine GIS Internet Data Catalog.

Standard Order Process:

Available Time Period:

Time Period Information:

Range of Dates/Times:

Beginning Date: 12/31/1999
Beginning Time: Unknown
Ending Date: Present
Ending Time: Unknown

Distributor:

Contact Information:

Contact Organization Primary:

Contact Organization: (MEGIS) Maine Office of Geographic Information Systems

Contact Position: GIS Coordinator
Contact Address:

Address Type: mailing address
Address: State House Station 145
City: Augusta
State or Province: ME
Postal Code: 04333-0145
Country: USA

Contact Voice Telephone: (207) 624-7700
Contact Facsimile Telephone: (207) 287-3842
Hours of Service: Monday through Friday 0800 - 1700 EST

Distribution Liability: Users must assume responsibility to determine the usability of this data for their purposes.
Standard Order Process:

Digital Form:

Digital Transfer Information:

Format Name: ARCSDE
Format Version Number: ArcSDE 9.x
Format Information Content: Oracle 9i

Digital Transfer Option:

Online Option:

Access Instructions: Please contact the Maine Office of GIS (MEGIS) for access instructions.

Fees: Access is available through Maine's wide area network; WAN users may contact the Maine Office of Information Technology, Maine Office of Geographic Information Systems (MEGIS) for a login.

Metadata Date: 7/1/2000
Metadata Review Date: 9/25/2007
Metadata Future Review Date:
Metadata Contact:

Contact Information:

Contact Organization Primary:

Contact Organization: Maine Office of Geographic Information Systems

Contact Position: GIS Coordinator
Contact Address:

Address Type: mailing address
Address: State House Station 145
City: Augusta
State or Province: ME
Postal Code: 04333-0145
Country: USA

Contact Voice Telephone: 207 624-7700
Contact Facsimile Telephone: 207 287-4563
Hours of Service: Monday through Friday 0800 - 1700 EST

Metadata Standard Name:
FGDC Content Standards for Digital Geospatial Metadata Metadata

Metadata Standard Version: FGDC-STD-001-1998
Metadata Access Constraints: None
Metadata Use Constraints: None