medoq

Citation:

Citation Information:

Originator: U.S. Geological Survey (USGS), Maine Office of Geographic Information Systems (MEGIS) (comp., ed.)
Publication Date: 20010131
Publication Time: Unknown
Title: medoq
Geospatial Data Presentation Form: remote sensing image
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:
For additional information contact MEGIS at 1-207-287-6144. MEDOQ flight dates are available in comma delimited text, and .dbf format, on the MEGIS Data Catalog at http://megis.maine.gov/catalog/ "Tables" link medoqmeta.zip and in the REGIONS dataset MEDOQINDEX, a spatial index of MEDOQ image numbers by 1:24000 scale tile.
Online Linkage: http://megis.maine.gov/catalog/

Description:

Abstract:
MEDOQ are digital orthorectified aerial imagery in gray-scale with 1-meter ground resolution. They are derived from the original US Geological Survey Digital Orthophoto Quarter Quads but cover one full 7.5 minute quadrangle. MEDOQs are compressed using the Lizardtech MrSid software (http://www.lizardtech.com) and are referred to as MrSid format ( .sid ) imagery. The MEDOQs are suitable for applications at a scale of 1" = 1,000 ( 1:12,000 ). MEDOQs are now available for all of Maine on the Maine Office of GIS Data Catalog website at http://megis.maine.gov/catalog/ MEDOQs in the northwestern parts of Maine are not visible yet on the MEGIS website Aerial Photography Viewer.
Purpose:
MEDOQs are are suitable for applications at a scale of 1" = 1,000 ( 1:12,000 ) or larger. According to National Map Accuracy Standards for maps at that scale 90% of well defined points tested must be within 1/30 of an inch or 33.33 feet of their true position on the ground. DOQs serve a variety of purposes, from interim maps to field references for earth science investigations and analysis. The DOQ is useful as a layer of a geographic information system and as a tool for revision of digital line graphs and topographic maps.Users must assume responsibility in determining the usability of this data for their purpose. Data at this scale may be useful for parcel level studies and detailed planning.
Supplemental Information:
Information in this document was drawn, compiled and modified to fit this data presentation from: USGS. 1998. Metadata for Digital Orthophoto Quadrangles. September 28, 1998, Reston VA. For more information see: http://mac.usgs.gov/. Dataset searching and ordering capabilities are available through EarthExplorer at URL http://earthexplorer.usgs.gov .
Time Period of Content:

Time Period Information:

Range of Dates/Times:

Beginning Date: 1996
Beginning Time: Unknown
Ending Date: 1998
Ending Time: Unknown

Currentness Reference: source dates

Status:

Progress: Complete
Maintenance and Update Frequency: none planned

Spatial Domain:

Bounding Coordinates:

West Bounding Coordinate: -71.24604
East Bounding Coordinate: -66.8
North Bounding Coordinate: 47.6
South Bounding Coordinate: 42.90479

Keywords:

Theme:

Theme Keyword Thesaurus: ISO Keyword Thesaurus
Theme Keyword: imageryBaseMapsEarthCover

Theme:

Theme Keyword Thesaurus: Maine GIS Thesaurus-Theme
Theme Keyword: digital orthophotoquad
Theme Keyword: doq
Theme Keyword: aerial photograph

Place:

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

Stratum:

Stratum Keyword Thesaurus: GCMD Parameter Keyword
Stratum Keyword: land surface
Stratum Keyword: radiance or imagery

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 server ArcInfo version 9.3, Solaris, MrSid
Cross Reference:

Citation Information:

Originator: Maine Office of Geographic Information Systems (MEGIS)(comp.)
Publication Date: 20020409
Title: MEDOQMETA
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/

Cross Reference:

Citation Information:

Originator: Maine Office of Geographic Information Systems (MEGIS)
Publication Date: 20041001
Publication Time: Unknown
Title: medoqindex
Geospatial Data Presentation Form: vector 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 (MEGIS)

Other Citation Details: 1:24000
Online Linkage: http://megis.maine.gov/catalog/

Attribute Accuracy:

Attribute Accuracy Report:
During photographic reproduction of the source photography, limited analog dodging is performed to improve image quality. Analog dodging consists of holding back light from certain areas of the sensitized photographic material to avoid overexposure. The diapositive is inspected to insure clarity and radiometric uniformity. Diapositive image brightness values are collected with a minimum of image quality manipulation. Image brightness values may deviate from brightness values of the original imagery due to image value interpolation during the scanning and rectification processes. Radiometry is verified by visual inspection of the digital orthophoto quadrangle with the original unrectified image to determine if the digital orthophoto has the same or better image quality as the original unrectified input image. Slight systematic radiometric differences can be detected between adjacent DOQ files due primarily to differences in source photography capture dates and sun angles of aerial photography along flight lines. These differences can be observed in an image's general lightness or darkness when compared to adjacent DOQ file coverages.
Logical Consistency Report:
All DOQ header data and image file sizes are validated by the Tape Validation System (TVS) software prior to archiving in the National Digital Cartographic Data Base (NDCDB). This validation procedure assures correct physical format and field values for header record elements. Logical relationships between header record elements are tested.
Completeness Report:
USGS DOQQs are available for most of eastern Maine and are available here as MEDOQs. Western Maine DOQQs are currently under development at USGS, (http://mcmcweb.er.usgs.gov/status/mac/me/index.html#doq), expected delivery is 2002. All DOQ imagery is visually inspected for completeness to ensure that no gaps, or image misplacement exist in the 3.75' image area or in overedge coverage. DOQ images may be derived by mosaicking multiple images, in order to insure complete coverage. All DOQs are cloud free within the 3.75' image area. Some clouds may, very infrequently, be encountered only in the overedge coverage. Source photography is leaf-off in deciduous vegetation regions. Void areas having a radiometric value of zero and appearing black may exist. These are areas for which no photographic source is available or result from image transformation from other planimetric systems to the Universal Transverse Mercator (UTM). In the latter case, the void sliver areas are on the outside edges of the overedge area. The data set field content of each DOQ header record element is validated to assure completeness prior to archiving in the NDCDB.
Positional Accuracy:

Horizontal Positional Accuracy:

Horizontal Positional Accuracy Report:
The DOQ horizontal positional accuracy and the assurance of that accuracy depend, in part, on the accuracy of the data inputs to the rectification process. These inputs consist of the digital elevation model (DEM),aerotriangulation control and methods, the photo source camera calibration, scanner calibration, and aerial photographs that meet National Aerial Photography Program (NAPP) standards. The vertical accuracy of the verified USGS format DEM is equivalent to or better than a USGS level 1 or 2 DEM, with a root mean square error (RMSE) of no greater than 7.0 meters. Field control is acquired by third order class 1 or better survey methods sufficiently spaced to meet National Map Accuracy Standards (NMAS) for 1:12,000-scale products. Aerial cameras have current certification from the USGS, National Mapping Division, Optical Science Laboratory. Test calibration scans are performed on all source photography scanners.
Quantitative Horizontal Positional Accuracy Assessment:

Horizontal Positional Accuracy Value: 10
Horizontal Positional Accuracy Explanation:
Field control is acquired by third order class 1 or better survey methods sufficiently spaced to meet National Map Accuracy Standards (NMAS) for 1:12,000-scale products. Aerial cameras have current certification from the USGS, National Mapping Division, Optical Science Laboratory. Test calibration scans are performed on all source photography scanners.
Vertical Positional Accuracy:

Vertical Positional Accuracy Report: The DOQ accuracy depend, in part, on the accuracy of the data inputs to the rectification process. These inputs include digital elevation models (DEM).
Quantitative Vertical Positional Accuracy Assessment:

Vertical Positional Accuracy Value: 7
Vertical Positional Accuracy Explanation:
DEM aerotriangulation control and methods, the photo source camera calibration, scanner calibration, and aerial photographs that meet National Aerial Photography Program (NAPP) standards. The vertical accuracy of the verified USGS format DEM is equivalent to or better than a USGS level 1 or 2 DEM, with a root mean square error (RMSE) of no greater than 7.0 meters.
Lineage:

Source Information:

Source Citation:

Citation Information:

Originator: U.S. Geological Survey (USGS)
Publication Date: 1995
Publication Time: Unknown
Title: (250kdem) USGS 1:250,000 scale digital elevation models
Geospatial Data Presentation Form: raster digital data
Series Information:

Series Name: USGS Digital Elevation Models
Issue Identification: 1:250000 DEM

Publication Information:

Publication Place: Reston VA
Publisher: U.S. Geological Survey

Other Citation Details:
3- x 3-arc second DEMS provides coverage in 1 x 1 degree blocks for all the contiguous United States, Hawaii and limited parts of Alaska. The basic elevation model is produced by or for the U.S. Department of Defense, Defense Mapping Agency (DMA), but is distributed by the USGS, EROS Data Center, in the DEM data record format. 1:250000 Digital Elevation Model data
Online Linkage: http://mapping.usgs.gov/mac/isb/pubs/factsheets/fs04000.html

Source Scale Denominator: 250000
Type of Source Media: digital tape media
Source Time Period of Content:

Time Period Information:

Single Date/Time:

Calendar Date: 1995
Time of Day: Unknown

Source Currentness Reference: publication date

Source Citation Abbreviation: 250kdem
Source Contribution: Elevation data in the form of an ortho-DEM regridded to user-specified intervals and bounds.

Source Information:

Source Citation:

Citation Information:

Originator: U.S. Geological Survey (USGS)
Publication Date: 19870101
Publication Time: Unknown
Title: (NAPP) National Aerial Photography Program
Geospatial Data Presentation Form: aerial photograph
Series Information:

Series Name: National Aerial Photography Program
Issue Identification: 1987, 1992, 1997

Publication Information:

Publication Place: Reston VA
Publisher: U.S. Geological Survey

Other Citation Details:
NAPP photography is acquired at 20,000 feet above mean terrain with a 6 inch focal length lens. The flight lines are quarter quad-centered on the 1:24,000-scale USGS maps. NAPP photographs have an approximate scale of 1:40,000, and are flown in black-and-white or color infrared, depending on state or federal requirements. NAPP photography is indexed on 1:100,000-scale USGS maps.
Online Linkage: http://edc.usgs.gov/glis/hyper/guide/napp

Source Scale Denominator: 40000
Type of Source Media: paper and online
Source Time Period of Content:

Time Period Information:

Range of Dates/Times:

Beginning Date: 1/1/1987
Beginning Time: Unknown
Ending Date: Present
Ending Time: Unknown

Source Currentness Reference: publication date

Source Citation Abbreviation: napp
Source Contribution: Panchromatic black and white (or color infra-red) NAPP or NAPP-like photograph. NAPP photographs are centered on the DOQ coverage area.

Source Information:

Source Citation:

Citation Information:

Originator: U.S. Geological Survey
Publication Date: multiple dates
Publication Time: Unknown
Title: (DOQQ) Digital Orthophoto Quarter Quadrangles
Geospatial Data Presentation Form: remote-sensing image
Publication Information:

Publication Place: Reston VA
Publisher: U.S. Geological Survey

Other Citation Details:
Orthophotos combine the image characteristics of a photograph with the geometric qualities of a map. The primary digital orthophotoquad (DOQ) is a 1-meter ground resolution, quarter-quadrangle (3.75-minutes of latitude by 3.75-minutes of longitude) image cast on the Universal Transverse Mercator Projection (UTM) on the North American Datum of 1983 (NAD83).The geographic extent of the DOQ is equivalent to a quarter-quad plus The overedge ranges a minimum of 50 meters to a maximum of 300 meters beyond the extremes of the primary and secondary corner points. The overedge is included to facilitate tonal matching for mosaicking and for the placement of the NAD83 and secondary datum corner ticks. The normal orientation of data is by lines (rows) and samples (columns). Each line contains a series of pixels ordered from west to east with the order of the lines from north to south. The standard, archived digital orthophoto is formatted as four ASCII header records, followed by a series of 8-bit binary image data records. The radiometric image brightness values are stored as 256 gray levels ranging from 0 to 255. The metadata provided in the digital orthophoto contain a wide range of descriptive information including format source information, production instrumentation and dates, and data to assist with displaying and georeferencing the image. The standard distribution format of DOQs will be JPEG compressed images. U.S. Department of the Interior, U.S. Geological Survey, 1992, Standards for digital orthophotos: Reston, VA. A hypertext version is available at: <URL: http://mapping.usgs.gov/www/ti/DOQ/standards_doq.html> Softcopy in WordPerfect format is available at: <URL: ftp://mapping.usgs.gov/pub/ti/DOQ/doqstnds/doq1_12-96.wp6> <URL: ftp://mapping.usgs.gov/pub/ti/DOQ/doqstnds/doq2_12-96.wp6 Softcopy in Portable Document Format (PDF) is available at: <URL: ftp://mapping.usgs.gov/pub/ti/DOQ/doqstnds/usgsdoq.pdf>
Source Scale Denominator: 12000
Type of Source Media: CD-ROM
Source Time Period of Content:

Time Period Information:

Range of Dates/Times:

Beginning Date: 1997
Beginning Time: Unknown
Ending Date: Present
Ending Time: Unknown

Source Currentness Reference: publication date

Source Citation Abbreviation: doqq
Source Contribution: DOQQs were appended to assemble MEGIS tiled MEDOQs.

Process Step:

Process Description:
The production procedures, instrumentation, hardware and software used in the collection of standard USGS DOQs vary depending on systems used at the contract, cooperator or USGS production sites. The majority of DOQ datasets are acquired through government contract. The process step describes, in general, the process used in the production of standard USGS DOQ data sets. The rectification process requires, as input, a user parameter file to control the rectification process, a digital elevation model (DEM1) gridded to user specified bounds, projection, zone, datum and X-Y units, a scanned digital image file (PHOTO1) covering the same area as the DEM, ground X-Y-Z point values (CONTROL_INPUT) and their conjugate photo coordinates in the camera coordinate system, and measurements of the fiducial marks (CAMERA_INPUT) in the digitized image. The camera calibration report (CAMERA_INPUT) provides the focal length of the camera and the distances in millimeters from the camera's optical center to the camera's 8 fiducial marks. These marks define the frame of reference for spatial measurements made from the photograph. Ground control points (CONTROL_INPUT) acquired from ground surveys or developed in aerotriangulation, are third order class 1 or better, and meet National Map Accuracy Standard (NMAS) for 1:12,000-scale. Ground control points are in the Universal Transverse Mercator or the State Plane Coordinate System on NAD83. Horizontal and vertical residuals of aerotriangulated tie-points are equal to or less than 2.5 meters. Standard aerotriangulation passpoint configuration consists of 9 ground control points, one near each corner, one at the center near each side and 1 near the center of the photograph, are used. The conjugate positions of the ground control points on the photograph are measured and recorded in camera coordinates. The raster image file (PHOTO_1) is created by scanning an aerial photograph film diapositive with a precision image scanner. An aperture of approximately 25 to 32 microns is used, with an aperture no greater than 32 microns permitted. Using 1:40,000-scale photographs, a 25-micron scan aperture equates to a ground resolution of 1-meter. The scanner converts the photographic image densities to gray scale values ranging from 0 to 255 for black and white photographs. Scan files with ground resolution less than 1 meter or greater than 1 meter but less than 1.28 meters are resampled to 1 meter. The principal elevation data source (DEM1) are standard DEM datasets from the National Digital Cartographic Data Base (NDCDB). DEMs that meet USGS standards are also produced by contractors to fulfill DOQ production requirements and are subsequently archived in the NDCDB. All DEM data is equivalent to or better than USGS DEM standard level 1. The DEM used in the production of DOQs generally has a 30-meter grid post spacing and possesses a vertical RMSE of 7-meters or less. A DEM covering the extent of the photograph is used for the rectification. The DEM is traversed from user-selected minimum to maximum X-Y values and the DEM X-Y-Z values are used to find pixel coordinates in the digitized photograph using transformations mentioned above. For each raster image cell subdivision, a brightness or gray-scale value is obtained using nearest neighbor, bilinear, or cubic convolution resampling of the scanned image. The pixel processing algorithm is indicated in the header file. An inverse transformation relates the image coordinates referenced to the fiducial coordinate space back to scanner coordinate space. For those areas for which a 7.5-minute DEM is unavailable and relief differences are less than 150 feet, a planar-DEM(slope-plane substitute grid) may be used.
Source Used Citation Abbreviation: 250kdem
Source Used Citation Abbreviation: napp
Source Produced Citation Abbreviation: doqq
Process Contact:

Contact Information:

Contact Organization Primary:

Contact Organization: (USGSGNIS) US Geological Survey

Contact Position: Chief, Geographic Names Information Section
Contact Address:

Address Type: mailing and physical address
Address: 523 National Center
City: Reston
State or Province: VA
Postal Code: 20192
Country: USA

Contact Voice Telephone: (703) 648-4551
Contact Electronic Mail Address: rwrocest@usgs.gov

Process Step:

Process Description:
Rectification Process: The photo control points and focal length are iteratively fitted to their conjugate ground control points using a single photo space resection equation. From this mathematical fit is obtained a rotation matrix of constants about the three axes of the camera. This rotation matrix can then be used to find the photograph or camera coordinates of any other ground X-Y-Z point. Next a two dimensional fit is made between the measured fiducial marks on the digitized photograph and their conjugate camera coordinates. Transformation constants are developed from the fit and the camera or photo coordinates are used in reverse to find their conjugate pixel coordinates on the digitized photograph.
Process Contact:

Contact Information:

Contact Organization Primary:

Contact Organization: (USGSGNIS) US Geological Survey

Contact Position: Chief, Geographic Names Information Section
Contact Address:

Address Type: mailing and physical address
Address: 523 National Center
City: Reston
State or Province: VA
Postal Code: 20192
Country: USA

Contact Voice Telephone: (703) 648-4551
Contact Electronic Mail Address: rwrocest@usgs.gov

Process Step:

Process Description:
Quality Control: All data is inspected according to a quality control plan. DOQ contractors must meet DOQ standards for attribute accuracy, logical consistency, data completeness and horizontal positional accuracy. During the initial production phase, all rectification inputs and DOQ data sets are inspected for conformance to standards. After a production source demonstrates high quality, inspections will be made to 10% of delivery lots (40 DOQs per lot). All DOQs are visually inspected for gross positional errors and tested for physical format standards.
Process Contact:

Contact Information:

Contact Organization Primary:

Contact Organization: (USGSGNIS) US Geological Survey

Contact Position: Chief, Geographic Names Information Section
Contact Address:

Address Type: mailing and physical address
Address: 523 National Center
City: Reston
State or Province: VA
Postal Code: 20192
Country: USA

Contact Voice Telephone: (703) 648-4551
Contact Electronic Mail Address: rwrocest@usgs.gov

Process Step:

Process Description:
The Maine Office of GIS used the MrSid Workstation Geospatial Encoder 1.3.1 from Lizardtech, Inc. (http://www.lizardtech.com/index.html), to compress and mosaic the USGS DOQs. The USGS DOQs were copied to the Maine Office of GIS server and then the four quarter quads (DOQQs) that make up one quad were added into MrSid to compress and mosaic together. All images were compressed using the same tolerances in MrSid: a target compression ratio of 12:1, 5 zoom levels, a target thumbnail of 500 pixels, and a block size of 512. The typical input of the four quarter quads added up to approximately 165MB and the typical MrSid output was approximately 12.5MB per quad. The majority of the images were viewed before the mosaic process was completed so the best order to overlap the images that would result in the least of amount of data loss in overlapping areas could be determined. Due to the time-consuming nature of this image comparison procedure it was not performed on all images. MrSid images were created so that MEGIS could store all of the available images on the MEGIS server and also to provide a manageable data size for distribution from the MEGIS website.
Source Used Citation Abbreviation: doqq
Process Date: 20001116
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: The MrSid DOQ image (MEDOQ) for the Monhegan Quad has been updated. The southern half of the older image was registered incorrectly and we recently received replacement images from USGS.
Process Date: 20020902
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: 628 image mosaic Maine
Direct Spatial Reference Method: Raster
Raster Object Information:

Raster Object Type: Pixel
Row Count: 492758
Column Count: 334280

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:
MEDOQs are georeferenced compressed images of Maine based on USGS DOQQs and in USGS quadrangles extent. For DOQs from panchromatic source each pixel contains an 8-bit gray-scale value between 0-255. A value of 0 represents the color black while a value of 255 represents the color white. All values between 0 and 255 are repesented as a shade of gray varying from black to white. For color-infrared and natural color DOQs a digital number from 0 to 255 will also be assigned to each pixel but that number will refer to a color look-up table which will contain the RGB red, blue and green (RGB) values, each from 0 to 255, for that digital number. Areas where the rectification process is incomplete due to incomplete data (i.e., lack of elevation data, gaps), are represented with the numeric value of 0. MEDOQ flight dates are available in comma delimited text, and .dbf format, on the Maine GIS Data Catalog at http://megis.maine.gov/catalog "Tables".
Entity and Attribute Detail Citation:
U.S. Department of the Interior, U.S. Geological Survey, 1992, Standards for digital orthophotos: Reston, VA. A hypertext version is available at: <URL: http://mapping.usgs.gov/www/ti/DOQ/standards_doq.html> Softcopy in WordPerfect format is available at: <URL: ftp://mapping.usgs.gov/pub/ti/DOQ/doqstnds/doq1_12-96.wp6> <URL: ftp://mapping.usgs.gov/pub/ti/DOQ/doqstnds/doq2_12-96.wp6 Softcopy in Portable Document Format (PDF) is available at: <URL: ftp://mapping.usgs.gov/pub/ti/DOQ/doqstnds/usgsdoq.pdf>

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: MrSID
Format Version Number: 1.3.1 Geospatial Encoder
Format Specification: Portable Image Format
Format Information Content:
Multiple options exist for viewing images in MrSID format which consist of .sid and .sdw georeferencing files. For the GIS community, viewers exist for or are built into ArcView, ArcInfo Desktop 9.x, MapInfo, MapObjects, GeoMedia, IRAS-C, cadcorp Map Modeller, MicroStation, Photoshop, and other major imaging applications.
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/links/ . Files compressed with MrSID software are usable in many GIS environments, by default or by extension. If you are not already a GIS user, a link to free software for viewing of these files, ArcExplorer from Environmental Systems Research Institute, Inc. (ESRI), is available at http://megis.maine.gov/links/ . Trial viewing software for MrSID files is also available from the software developer LizardTech at http://www.lizardtech.com/download/dl_download.php?detail=geo_geoexpressview&platform=win .
Digital Transfer Option:

Online Option:

Computer Contact Information:

Network Address:

Network Resource Name: ftp://ftp.state.me.us/outgoing

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.

Standard Order Process:

Available Time Period:

Time Period Information:

Range of Dates/Times:

Beginning Date: 1/31/2001
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.

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: WMS
Format Version Number: 1.1
Format Specification: OpenGIS (OGC) Web Map Service (WMS )
Format Information Content:
MEGIS has created a web based application for Maine GIS data that adheres to the OpenGIS Consortium (OGC) Web Mapping Specification (WMS 1.1.1) which allows map servers to create and send standard map images over the Web.
Digital Transfer Option:

Online Option:

Computer Contact Information:

Network Address:

Network Resource Name: http://megisims.state.me.us/wmsconnector/com.esri.wms.Esrimap/WMSFramework?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&LAYERS=DOQQ&SRS=EPSG:4326&BBOX=-71.31,42.85,-66.74,47.67&WIDTH=400&HEIGHT=300&FORMAT=image/png&STYLES=
Network Resource Name: http://megisims.state.me.us/wmsconnector/com.esri.wms.Esrimap/WMSFramework?request=getcapabilities&service=WMS&version=1.1.1
Network Resource Name: http://megisims.state.me.us/wmsconnector/com.esri.wms.Esrimap/WMSFramework?

Access Instructions: This metadata document contains embedded URLs that can be used to make OGC WMS 1.1.1 compliant map requests of the framework layers in the Maine GeoLibrary.

Fees: None
Ordering Instructions:
Currently OGC WMS 1.1.1 access is available for CONTOURS, DOQQ, E911RDS, HYD24L, HYD24P, INDEX_HF, MECNSLND, MEDOQINDEX, MEDOTPUB, MERAIL24, METWP24L, METWP24P, ORTHO_HF, ORTHO_FF, ORTHO_1F, ORTHO_2F, INDEX_FF, INDEX_1F, INDEX_2F, OTRANS. These images are available to the Web and client software for overlay and display of multiple maps using first of the URLS listed above. Access the OGC: WMS Framework "WMT_MS Get Capabilities" in XML using Internet browser or other XML friendly viewer.

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