ÿþ<html> <head> <META http-equiv="Content-Type" content="text/html; charset=UTF-16"> <title>Connecticut 1990 Orthophoto</title> <link rel="schema.dc" href="http://dublincore.org/documents/dces/"> <meta name="dc.title" content="Connecticut 1990 Orthophoto"> <meta name="dc.title" content="1990 Digital Orthophoto Quarter Quadrangles (DOQQ)"> <meta name="dc.creator" content="State of Connecticut, Department of Environmental Protection (data publisher)"> <meta name="dc.creator" content="U.S. Geological Survey (original data compiler, editor and publisher)"> <meta name="dc.creator" content="State of Connecticut, Department of Environmental Protection (data publisher)"> <meta name="dc.creator" content="U.S. Geological Survey (original data compiler, editor, and publisher)"> <meta name="dc.subject" content="biota elevation imageryBaseMapsEarthCover inlandWaters geoscientificInformation oceans society USGS digital orthophoto quad 1-Meter DOQ DOQ DOQQ digital orthophoto quadrangle digital orthophoto quarter quadrangle orthophoto orthophotography orthoimage orthoimagery imagery raster geo-referenced raster image aerial photo"> <meta name="dc.description" content="Connecticut 1990 Orthophoto is a raster mosaic of 1990 orthophotography for Connecticut. It represents a mosaic of 414 digital orthophoto quarter quads (DOQQ) produced by the U.S. Geological Survey (USGS). The date of the orthophotography is 1990. The raster mosaic is based on DOQQs that are gray-scale, leaf-off, 1:12,000 scale (1 inch = 1,000 feet), quarter-quadrangle (3.75 minutes of latitude by 3.75 minutes of longitude) input raster images with 1-meter ground resolution. Input raster DOQQs are in Tagged Image File Format (TIFF) format and named &quot;ortho_1990_quad0078se.tif&quot; after CT DEP quadrangle number 78, SE quadrant, for example. Each 7.5 minute quadrangle is broken into four quadrants: NE, NW, SE, and SW. Each of these 3.75 minute quarter quadrangles is referred to as a quarter quad. Orthophotos combine the image characteristics of a photograph with the geometric qualities of a map. The primary orthophoto produced by the USGS is the digital orthophoto quarter quadrangle (DOQQ), 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 DOQQ is equivalent to a quarter-quadrangle plus the overedge ranges from a minimum of 50 meters to a maximum of 300 meters 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 radiometric image brightness values are stored as 256 gray levels, ranging from 0 to 255."> <meta name="dc.publisher" content="State of Connecticut, Department of Environmental Protection"> <meta name="dc.date" content="20070402"> <meta name="dc.type" content="data.Fgdb raster digital data"> <meta name="dc.format" content="File Geodatabase Raster Dataset"> <meta name="dc.identifier" content="http://www.ct.gov/dep"> <meta name="dc.source" content="Connecticut 1990 Orthophoto"> <meta name="dc.lang" content="en"> <meta name="dc.coverage.x.min" scheme="DD" content="-73.766497"> <meta name="dc.coverage.x.max" scheme="DD" content="-71.739317"> <meta name="dc.coverage.y.min" scheme="DD" content="40.936016"> <meta name="dc.coverage.y.max" scheme="DD" content="42.066805"> <meta name="dc.coverage.placeName" content="Connecticut"> <meta name="dc.coverage.placeName" content="CT"> <meta name="dc.rights" content="Access constraints: None. No restrictions or legal prerequisites for accessing the data. The data is in the public domain and may be redistributed.; Use constraints: None. No restrictions or legal prerequisites for using the data after access is granted. The data is suitable for use at appropriate scale, and is not intended for maps printed at scales greater or more detailed than 1:12,000 scale (1 inch = 1,000 feet). Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the CT DEP and the USGS as the source for this information. For example, include the following data source description when printing this information on a map: 1990 Orthophotos - From USGS DOQQ. Source map scale is 1:12,000. Acknowledgement of the U.S. Geological Survey is appreciated in products derived from these data."><script type="text/javascript" language="JavaScript1.3"> /* Onload - Find each <pre> element with an Id="fixvalue" and call fixvalue() function to parse text to respect line breaks, replace <pre> element with <div> elememt, and convert URL address strings in text to <a href> element. */ window.onload = function() { elem = document.getElementById("fixvalue"); while (Boolean(elem != null)) { fixvalue(elem); elem = document.getElementById("fixvalue"); } window.focus() } /* Fix value - Parse text in <pre> element to respect line breaks introduced in ArcCatalog by the metadata author who intentionally introduced single line breaks to start new lines or even more than one consecutive line break to further separate text to form paragraphs. 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For example the ")" in ")," var nexttolastchar = fullurl.charAt(fullurl.length - 2); if (nexttolastchar.match(punctuation) != null) { url = fullurl.substring(0,fullurl.length - 2); } else { url = fullurl.substring(0,fullurl.length - 1); } } start = (result.index + url.length) // Test to concatinate 'http://' to url if not already begininng with 'http://', 'https://' or 'ftp://'" if (protocol == "") { url = "http://" + url; } // Append Hypertext (anchor) Element to parent elemText = document.createTextNode(url); var elemAnchor = document.createElement("A"); elemAnchor.setAttribute("href", url); elemAnchor.setAttribute("target", "viewer"); elemAnchor.appendChild(elemText); elem.appendChild(elemAnchor); } end = txt.length; if (start < end) { // Append Text Node that follows last Hypertext Element elemText = document.createTextNode(txt.substring(start, end)); elem.appendChild(elemText); } } </script></head> <body> <div style="text-align:right; width:100%"> <a href="FileGDB_ortho_1990_FGDC_Classic.htm">FGDC Classic</a> |FGDC FAQ | <a href="FileGDB_ortho_1990_FGDC_Plus.htm">FGDC Plus</a> | <a href="FileGDB_ortho_1990.xml">XML</a></div> <hr> <h1>Connecticut 1990 Orthophoto</h1> <h2>Frequently-asked questions:</h2> <ul> <li><a href="#what">What does this data set describe?</a><ol> <li><a href="#what.1">How should this data set be cited?</a></li> <li><a href="#what.2">What geographic area does the data set cover?</a></li> <li><a href="#what.3">What does it look like?</a></li> <li><a href="#what.4">Does the data set describe conditions during a particular time period?</a></li> <li><a href="#what.5">What is the general form of this data set?</a></li> <li><a href="#what.6">How does the data set represent geographic features?</a></li> <li><a href="#what.7">How does the data set describe geographic features?</a></li> </ol> </li> <li><a href="#who">Who produced the data set?</a><ol> <li><a href="#who.1">Who are the originators of the data set?</a></li> <li><a href="#who.2">Who also contributed to the data set?</a></li> <li><a href="#who.3">To whom should users address questions about the data?</a></li> </ol> </li> <li><a href="#why">Why was the data set created?</a></li> <li><a href="#how">How was the data set created?</a><ol> <li><a href="#how.1">Where did the data come from?</a></li> <li><a href="#how.2">What changes have been made?</a></li> </ol> </li> <li><a href="#quality">How reliable are the data; what problems remain in the data set?</a><ol> <li><a href="#quality.1">How well have the observations been checked?</a></li> <li><a href="#quality.2">How accurate are the geographic locations?</a></li> <li><a href="#quality.3">How accurate are the heights or depths?</a></li> <li><a href="#quality.4">Where are the gaps in the data? What is missing?</a></li> <li><a href="#quality.5">How consistent are the relationships among the data, including topology?</a></li> </ol> </li> <li><a href="#getacopy">How can someone get a copy of the data set?</a><ol> <li><a href="#getacopy.0">Are there legal restrictions on access or use of the data?</a></li> <li><a href="#getacopy.1">Who distributes the data?</a></li> <li><a href="#getacopy.2">What's the catalog number I need to order this data set?</a></li> <li><a href="#getacopy.3">What legal disclaimers am I supposed to read?</a></li> <li><a href="#getacopy.4">How can I download or order the data?</a></li> <li><a href="#getacopy.5">Is there some other way to get the data?</a></li> <li><a href="#getacopy.6">What hardware or software do I need in order to use the data set?</a></li> </ol> </li> <li><a href="#metaref">Who wrote the metadata?</a></li> </ul> <hr><a name="what"><h3>What does this data set describe?</h3></a><div style="margin-left:20"> <div><i>Title: </i></div> <div style="margin-left:40">Connecticut 1990 Orthophoto</div><br><div><i>Abstract: </i></div> <div style="margin-left:40"> <pre id="fixvalue">Connecticut 1990 Orthophoto is a raster mosaic of 1990 orthophotography for Connecticut. It represents a mosaic of 414 digital orthophoto quarter quads (DOQQ) produced by the U.S. Geological Survey (USGS). The date of the orthophotography is 1990. The raster mosaic is based on DOQQs that are gray-scale, leaf-off, 1:12,000 scale (1 inch = 1,000 feet), quarter-quadrangle (3.75 minutes of latitude by 3.75 minutes of longitude) input raster images with 1-meter ground resolution. Input raster DOQQs are in Tagged Image File Format (TIFF) format and named "ortho_1990_quad0078se.tif" after CT DEP quadrangle number 78, SE quadrant, for example. Each 7.5 minute quadrangle is broken into four quadrants: NE, NW, SE, and SW. Each of these 3.75 minute quarter quadrangles is referred to as a quarter quad. Orthophotos combine the image characteristics of a photograph with the geometric qualities of a map. The primary orthophoto produced by the USGS is the digital orthophoto quarter quadrangle (DOQQ), 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 DOQQ is equivalent to a quarter-quadrangle plus the overedge ranges from a minimum of 50 meters to a maximum of 300 meters 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 radiometric image brightness values are stored as 256 gray levels, ranging from 0 to 255.</pre> </div><br><div><i>Supplemental information: </i></div> <div style="margin-left:40"> <pre id="fixvalue">The Connecticut Department of Environmental Protection converted the 1990 DOQQs produced by the USGS from UTM (meters) to the Connecticut State Plane Coordinate System North American Datum of 1983 (NAD83). Map units are feet, not meters. These DOQQs are in Tagged Image File Format (TIFF) format and named ortho_1990_quadxxxxYY.tif, where xxxx is a 4 digit quadrangle number beginning at 0001 and YY identifies the quarter quadrange (ne, nw, se, sw). The Connecticut Department of Environmental Protection subsequently created a statewide mosaic of these 1990 DOQQs. An orthophoto or orthophotograph is an aerial photograph that has been geometrically corrected ("orthorectified") such that the scale of the photograph is uniform, meaning that the photo can be considered equivalent to a map. Unlike an aerial photograph, an orthophotograph can be used to measure true distances, because it is an accurate representation of the earth's surface, having been adjusted for topographic relief, lens distortion, and camera tilt. For additional specific information on the production of digital orthophoto quadrangles, refer to Standards for Digital Orthophotos (National Mapping Program Technical Instructions) published by the U.S. Department of Interior, U.S. Geological Survey, National Mapping Division.</pre> </div><br></div> <ol> <li><a name="what.1"><b>How should this data set be cited?</b></a><br><br><div style="margin-left:20; margin-right:40">State of Connecticut, Department of Environmental Protection (data publisher), U.S. Geological Survey (original data compiler, editor and publisher), 20070402, Connecticut 1990 Orthophoto: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, 06106. </div><br><div style="margin-left:20"><i>Online links: </i><ul> <li TYPE="disc"><a target="viewer" href="http://www.ct.gov/dep">http://www.ct.gov/dep</a></li> </ul><br></div> <div style="margin-left:20"> <div>This is part of the following larger work:</div><br><div style="margin-left:40"><div style="margin-left:20; margin-right:40">State of Connecticut, Department of Environmental Protection (data publisher), U.S. Geological Survey (original data compiler, editor, and publisher), 1990, 1990 Digital Orthophoto Quarter Quadrangles (DOQQ): USGS 3.75 Minute Digital Orthophoto Quarter Quadrangle (DOQQUSGS 3.75 Minute Digital Orthophoto Quarter Quadrangles (DOQQs) are othophotos that cover one quarter the area of a USGS 7.5 minute topographic quadrangle map., U.S. Geological Survey, Reston, Virgina 22092, USA. </div><br><div style="margin-left:20"><i>Online links: </i><ul> <li TYPE="disc"><a target="viewer" href="http://www.ct.gov/dep">http://www.ct.gov/dep</a></li> <li TYPE="disc"><a target="viewer" href="http://www.usgs.gov">http://www.usgs.gov</a></li> </ul><br></div> </div> </div> </li> <li><a name="what.2"><b>What geographic area does the data set cover?</b></a><br><br><div style="margin-left:20"> <div>Bounding coordinates:</div> <div style="margin-left:40"> <div><i>West: </i>-73.766497</div><div><i>East: </i>-71.739317</div><div><i>North: </i>42.066805</div><div><i>South: </i>40.936016</div></div> </div><br></li> <li><a name="what.3"><b>What does it look like?</b></a><br><br><div style="margin-left:20"> <div><a target="viewer" href="http://www.cteco.uconn.edu/metadata/dep/browsegraphic/orthophoto1990fullview.jpg">http://www.cteco.uconn.edu/metadata/dep/browsegraphic/orthophoto1990fullview.jpg</a> (JPEG) </div> <div style="margin-left:40">Full view of Connecticut 1990 Orthophoto</div> </div><br><div style="margin-left:20"> <div><a target="viewer" href="http://www.cteco.uconn.edu/metadata/dep/browsegraphic/orthophoto1990detailview.jpg">http://www.cteco.uconn.edu/metadata/dep/browsegraphic/orthophoto1990detailview.jpg</a> (JPEG) </div> <div style="margin-left:40">Detail view of Connecticut 1990 Color Orthophoto within vicinity of the University of Connecticut at Avery Point in Groton, Connecticut.</div> </div><br></li> <li><a name="what.4"><b>Does the data set describe conditions during a particular time period?</b></a><br><br><div style="margin-left:20"><i>Calendar date: </i>1990</div> <div style="margin-left:20"><i>Currentness reference: </i></div> <div style="margin-left:60"> <pre id="fixvalue">ground condition</pre> </div><br></li> <li><a name="what.5"><b>What is the general form of this data set?</b></a><br><br><div style="margin-left:20"><i>Geospatial data presentation form: </i>Fgdb raster digital data</div><br></li> <li><a name="what.6"><b>How does the data set represent geographic features?</b></a><br><br><ol TYPE="a"> <li><b>How are geographic features stored in the data set?</b><br><br><div style="margin-left:20"> This is a Raster data set. It contains the following raster data types: <ul> <li> Dimensions 125084 x 167755 x 1, type Pixel</li> </ul> </div><br></li> <li><b>What coordinate system is used to represent geographic features?</b><br><br><div style="margin-left:20"> <div>The map projection used is Lambert Conformal Conic.</div><br><div>Projection parameters: </div>Lambert Conformal Conic<div style="margin-left:40"> <div><i>Standard parallel: </i>41.200000</div> <div><i>Standard parallel: </i>41.866667</div> <div><i>Longitude of central meridian: </i>-72.750000</div> <div><i>Latitude of projection origin: </i>40.833333</div> <div><i>False easting: </i>999999.999996</div> <div><i>False northing: </i>499999.999998</div> </div><br><div>Planar coordinates are encoded using row and column.</div><div>Abscissae (x-coordinates) are specified to the nearest 3.281512.</div><div>Ordinates (y-coordinates) are specified to the nearest 3.281335.</div><div>Planar coordinates are specified in survey feet.</div><br><div>The horizontal datum used is North American Datum of 1983.</div><div>The ellipsoid used is Geodetic Reference System 80.</div><div>The semi-major axis of the ellipsoid used is 6378137.000000.</div><div>The flattening of the ellipsoid used is 1/298.257222.</div><br> Vertical coordinate system definition: <div style="margin-left:20"> Altitude system definition: <div style="margin-left:40"> <div><i>Altitude resolution: </i>1.000000</div><div><i>Altitude encoding method: </i>Explicit elevation coordinate included with horizontal coordinates</div></div> </div><br></div> </li> </ol> </li> <li><a name="what.7"><b>How does the data set describe geographic features?</b></a><br><br></li> </ol><a href="#Top">Back to Top</a><hr><a name="who"><h3>Who produced the data set?</h3></a><ol> <li><a name="who.1"><b>Who are the originators of the data set?</b> (may include formal authors, digital compilers, and editors)</a><br><br><ul> <li>State of Connecticut, Department of Environmental Protection (data publisher)</li> <li>U.S. Geological Survey (original data compiler, editor and publisher)</li> </ul><br></li> <li><a name="who.2"><b>Who also contributed to the data set?</b></a><br><br></li> <li><a name="who.3"><b>To whom should users address questions about the data?</b></a><br><br><div style="margin-left:20"> <div>Howie Sternberg</div><div>State of Connecticut, Department of Environmental Protection</div><div><pre id="fixvalue">79 Elm Street</pre></div> <div>Hartford, Connecticut 06106-5127</div> <div>USA</div><br><div>860-424-3540 (voice)</div><div>860-424-4058 (FAX)</div><div>dep.gisdata@po.state.ct.us </div><div><i>Hours of Service: </i>Monday to Friday, 08:30 to 16:30 Eastern Standard Time</div></div> </li> </ol><a href="#Top">Back to Top</a><hr><a name="why"><h3>Why was the data set created?</h3></a><div style="margin-left:20"> <pre id="fixvalue">DOQs (or DOQQs) 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 USGS digital line graphs and topographic maps. A DOQ can be incorporated into any geographic information system (GIS) that can manipulate raster images. It can function as a cartographic base for displaying, generating, and modifying associated digital planimetric data. Other applications include vegetation and timber management, routing and habitat analysis, environmental impact assessments, emergency evacuation planning, flood analysis, soil erosion assessment, facility management, and ground-water and watershed analysis. The accuracy and detail provided by the DOQ allow users to evaluate their data for accuracy and completeness, make real-time modifications to their data, and create new spatial data.</pre> </div><br><a href="#Top">Back to Top</a><hr><a name="how"><h3>How was the data set created?</h3></a><ol> <li><a name="how.1"><b>Where did the data come from?</b></a><br><br><div style="margin-left:20"> <div><b>DOQQ</b> (source 1 of 3) </div><br><div style="margin-left:20"> <div style="margin-left:20; margin-right:40">U.S. Geological Survey (original data compiler, editor and publisher), 1990, 1990 Digital Orthophoto Quarter Quad DOQQ - UTM: USGS Digital Orthophoto Quarter Quadrangles, U.S. Geological Suvey, Reston, Virgina 22092, USA. </div><br><div style="margin-left:20"><i>Online links: </i><ul> <li TYPE="disc"><a target="viewer" href="http://www.usgs.gov">http://www.usgs.gov</a></li> </ul><br></div> </div> <div style="margin-left:40"><i>Type of source media: </i>disc</div> <div style="margin-left:40"><i>Source scale denominator: </i>12000</div> <div style="margin-left:40"><i>Source contribution: </i></div> <div style="margin-left:80"> <pre id="fixvalue">1990 DOQQs for Connecticut produced by the USGS are gray-scale images with 1-meter ground resolution, UTM (NAD83). Image files are in Tagged Image File Format (TIFF) format.</pre> </div> </div><br><div style="margin-left:20"> <div><b>DOQQ Conn State Plane</b> (source 2 of 3) </div><br><div style="margin-left:20"> <div style="margin-left:20; margin-right:40">State of Connecticut, Department of Environmental Protection (data publisher), U.S. Geological Survey (original data compiler, editor and publisher), 1990, 1990 Digital Orthophoto Quarter Quad DOQQ - Conn State Plane. </div><br><div style="margin-left:20"><i>Online links: </i><ul> <li TYPE="disc"><a target="viewer" href="http://www.ct.gov/dep">http://www.ct.gov/dep</a></li> </ul><br></div> </div> <div style="margin-left:40"><i>Type of source media: </i>disc</div> <div style="margin-left:40"><i>Source scale denominator: </i>12000</div> <div style="margin-left:40"><i>Source contribution: </i></div> <div style="margin-left:80"> <pre id="fixvalue">These are copies of the 1990 DOQQs for Connecticut published by the USGS that have been converted to the Connecticut State Plane Coordinate System, North American Datum of 1983 (NAD83). Map units are feet, not meters. Image files are in Tagged Image File Format (TIFF) format and named ortho_1990_quadxxxxYY.tif, where xxxx is a 4 digit quadrangle number beginning at 0001 and YY identifies the quadrangle quadrange (ne, nw, se, sw). For example, the 4 DOQQs for the Hartford North CT quadrangle (quad 37) are ortho_1990_quad0037ne.tif (quad 37 northeast), ortho_1990_quad0037nw.tif (quad 37 northwest), ortho_1990_quad0037se.tif (quad 37 southeast), and ortho_1990_quad0037sw.tif (quad 37 southwest). </pre> </div> </div><br><div style="margin-left:20"> <div><b>ORTHOPHOTOMOSAIC</b> (source 3 of 3) </div><br><div style="margin-left:20"> <div style="margin-left:20; margin-right:40">State of Connecticut, Department of Environmental Protection, 20070402, Connecticut 1990 Orthophoto Mosaic: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut. </div><br></div> <div style="margin-left:40"><i>Type of source media: </i>disc</div> <div style="margin-left:40"><i>Source scale denominator: </i>12000</div> <div style="margin-left:40"><i>Source contribution: </i></div> <div style="margin-left:80"> <pre id="fixvalue">Statewide raster mosaic of all DOQQ Conn State Plane input rasters. The raster mosaic is in the Connecticut State Plane Coordinate System, North American Datum of 1983 (NAD83).</pre> </div> </div><br></li> <li><a name="how.2"><b>What changes have been made?</b></a><br><br><div style="margin-left:20"> <div><i>Date: </i>1999 (change 1 of 3) </div> <div style="margin-left:40"> <pre id="fixvalue">Primarily using ESRI ArcInfo 7 software, the Connecticut Department of Environmental Protection converted the DOQQs published by the USGS from UTM (meters) to the Connecticut State Plane Coordinate System North American Datum of 1983 (NAD83). Map units are feet, not meters. These DOQQs are in Tagged Image File Format (TIFF) format and named ortho_1990_quadxxxxYY.tif, where xxxx is a 4 digit quadrangle number beginning at 0001 and YY identifies the quarter quadrange (ne, nw, se, sw).</pre> </div><br><div style="margin-left:40"><i>Person responsible for change: </i><br><div style="margin-left:20"><div style="margin-left:20"> <div>Deborah Dumin</div><div>State of Connecticut, Department of Environmental Protection</div><div><pre id="fixvalue">79 Elm Street</pre></div> <div>Hartford, Connecticut 06106</div> <div>USA</div><br><div>860-424-3540 (voice)</div></div> </div> </div><br><div style="margin-left:40"><i>Data sources used in this process: </i><ul> <li TYPE="disc">DOQQ</li> </ul> </div><br><div style="margin-left:40"><i>Data sources produced in this process: </i><ul> <li TYPE="disc">DOQQ Conn State Plane</li> </ul> </div><br></div> <div style="margin-left:20"> <div><i>Date: </i>20070402 (change 2 of 3) </div> <div style="margin-left:40"> <pre id="fixvalue">Using ESRI ArcGIS 9.2 software, an empty raster dataset was created and subequently populated with input rasters to create a statewide raster mosaic. STEP 1 - Create Raster Dataset - The Coordinate System for the raster dataset is NAD_1983_StatePlane_Connecticut_FIPS_0600_Feet. The image compression type is JPEG with a compression quality of 90. The Pyramid Reference Point X and Y coordinate are 687800 and 1015180, respectively. Pyramids: 8 Bilinear. CreateRasterDataset "Database Connections\depdbs11_depraster_DEP_DirectConnect.sde" ORTHO_1990 # 8_BIT_UNSIGNED PROJCS['NAD_1983_StatePlane_Connecticut_FIPS_0600_Feet', GEOGCS['GCS_North_American_1983', DATUM['D_North_American_1983', SPHEROID['GRS_1980',6378137.0,298.257222101]], PRIMEM['Greenwich',0.0], UNIT['Degree',0.0174532925199433]], PROJECTION['Lambert_Conformal_Conic'], PARAMETER['False_Easting',999999.999996], PARAMETER['False_Northing',499999.999998], PARAMETER['Central_Meridian',-72.75], PARAMETER['Standard_Parallel_1',41.2], PARAMETER['Standard_Parallel_2',41.86666666666667], PARAMETER['Latitude_Of_Origin',40.83333333333334], UNIT['Foot_US',0.3048006096012192]] 1 DEPRASTER "PYRAMIDS 8 BILINEAR" "128 128" "JPEG 90" "687800 1015180" "Database Connections\depdbs11_depraster_DEP_DirectConnect.sde\depgisraster.DEP.ORTHO_1990" STEP 2 - Mosaic 414 DOQQ input rasters. The Mosaicking Tolerance value was set to 0.2. Consequently, pixel values in the raster mosaic resulted from a resampling of pixels values from individual input rasters when the difference in alignment between input and mosaic (target) pixels exceeded 0.2 pixel width. If the alignment difference is less than 0.2 pixel width, an input pixel value is assigned to the nearby target pixel, and a shift is performed instead of resampling all target pixels. Below is an example usage of the ESRI Geoprocessing Mosaic command and arguments used to mosaic 4 quarter quadrangle input rasters for USGS quadrangle No 50. Mosaic :\tif_format\ortho_1990_quad0050ne.tif; Z:\tif_format\ortho_1990_quad0050nw.tif; Z:\tif_format\qortho_1990_quad0050se.tif; Z:\tif_format\ortho_1990_quad0050sw.tif "Database Connections\depdbs11_depraster_DEP_DirectConnect.sde\DEPGISRASTER.DEP.ORTHO_1990" LAST FIRST # # NONE 0.2 "Database Connections\depdbs11_depraster_DEP_DirectConnect.sde\DEPGISRASTER.DEP.ORTHO_1990"</pre> </div><br><div style="margin-left:40"><i>Person responsible for change: </i><br><div style="margin-left:20"><div style="margin-left:20"> <div>Howie Sternberg</div><div>State of Connecticut, Department of Environmental Protectino</div><div><pre id="fixvalue">79 Elm Street</pre></div> <div>Hartford, Connecticut 06106</div> <div>USA</div><br><div>860-424-3540 (voice)</div><div>860-424-4058 (FAX)</div></div> </div> </div><br><div style="margin-left:40"><i>Data sources used in this process: </i><ul> <li TYPE="disc">DOQQ Conn State Plane</li> </ul> </div><br><div style="margin-left:40"><i>Data sources produced in this process: </i><ul> <li TYPE="disc">ORTHOPHOTOMOSAIC</li> </ul> </div><br></div> <div style="margin-left:20"> <div><i>Date: </i>20070622 (change 3 of 3) </div> <div style="margin-left:40"> <pre id="fixvalue">Copied data from ArcSDE 9.1 raster dataset to FileGeodatabase 9.2 raster dataset format for data distribution purposes. The image properties for the FileGeodatabase 9.2 raster dataset are the same as those for the version of the data in ArcSDE. The image compression type is JPEG with a compression quality of 90. Pyramids: 8 Bilinear. The Pixel Type is 8_BIT_UNSIGNED, which supports index values from 0 to 255. Bands: 1. Raster statistics were not built. Below is a record of the ESRI Geoprocessing CopyRaster command and arguments used in copying the data. CopyRaster "Database Connections\10.18.8.94_depgisraster_DEP.sde\DEPGISRASTER.DEP.ORTHO_1990" C:\GIS\Geo_Data\Connecticut\Raster_Data\Ortho_1990\Connecticut_Raster_Data.gdb\Ortho_1990 # # # NONE NONE 8_BIT_UNSIGNED On 04/29/09 the FileGeodatabase was subsequently upgraded to version 9.3.</pre> </div><br><div style="margin-left:40"><i>Person responsible for change: </i><br><div style="margin-left:20"><div style="margin-left:20"> <div>Howie Sternberg</div><div>State of Connecticut, Department of Environmental Protection</div><div><pre id="fixvalue">79 Elm Street</pre></div> <div>Hartford, Connecticut 06106</div> <div>USA</div><br><div>860-424-3540 (voice)</div><div>860-424-4058 (FAX)</div></div> </div> </div><br><div style="margin-left:40"><i>Data sources used in this process: </i><ul> <li TYPE="disc">ORTHOPHOTOMOSAIC</li> </ul> </div><br><div style="margin-left:40"><i>Data sources produced in this process: </i><ul> <li TYPE="disc">ORTHOPHOTOMOSAIC</li> </ul> </div><br></div> </li> </ol><a href="#Top">Back to Top</a><hr><a name="quality"><h3>How reliable are the data; what problems remain in the data set?</h3></a><ol> <li><a name="quality.1"><b>How well have the observations been checked?</b></a><br><br><div style="margin-left:20"> <pre id="fixvalue">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 visually inspecting the DOQs to the original unrectified image to determine if the DOQ has the same image quality or better image quality than the original unrectified input image. Slight systematic and 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.</pre> </div><br></li> <li><a name="quality.2"><b>How accurate are the geographic locations?</b></a><br><br><div style="margin-left:20"> <pre id="fixvalue">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. Field control is acquired by third order class 1 or better survey methods sufficiently spaced to meet National Map Accuracy Standards for 1:12,000-scale (1 inch = 1,000 feet) 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. Horizontal positional accuracy is determined by the Orthophoto Accuracy (ORACC) software program for DOQ data produced by the National Mapping Division. The program determines the accuracy by finding the line and sample coordinates of the passpoints in the DOQ and fitting these to their ground coordinates to develop a root mean square error (RMSE). From 4 to 9 points are checked. As a further accuracy test, the image line and sample coordinates of the DEM corners are transformed and compared with the actual X,Y DEM corner values to determine if they are within the RMSE. Additional information on this testing procedure can be found in U.S. Department of the Interior, U.S. Geological Survey, 1993, Technical Instructions, ORACC Users Manual (draft): Reston, VA. Adjacent DOQ's, when displayed together in a common planimetric coordinate system, may exhibit slight positional discrepancies across common DOQ boundaries. Linear features, such as streets, may not be continuous. These edge mismatches, however, still conform to positional horizontal accuracy within the NMAS. Field investigations to validate DOQ positional accuracy reliabilty are periodically conducted by the USGS, National Mapping Division, Geometronics Standards Section. DOQ's produced by cooperators and contractors use similarly approved RMSE test procedures.</pre> </div><br></li> <li><a name="quality.3"><b>How accurate are the heights or depths?</b></a><br><br><div style="margin-left:20"> <pre id="fixvalue">The vertical accuracy of the verified USGS format DEM is equivalent to or better than a USGS level-1 or -2 DEM.</pre> </div><br></li> <li><a name="quality.4"><b>Where are the gaps in the data? What is missing?</b></a><br><br><div style="margin-left:20"> <pre id="fixvalue">All DOQ images are visually inspected for completeness to ensure that no gaps or image misplacement exists in the image area or in overedge coverage. The DOQ images may be derived by mosaicking multiple images, in order to insure complete coverage. All DOQs are cloud free. Some clouds may, very infrequently, be encountered only in the overedge coverage. Source photography is leaf-off in deciduous vegetation regions. Void areas may exist, having a radiometric value of zero and appearing black. These voids are areas for which no photographic source is available or are the result of image transformation from other planimetric systems to the UTM projection. 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 Sales Data Base.</pre> </div><br></li> <li><a name="quality.5"><b>How consistent are the relationships among the observations, including topology?</b></a><br><br><div style="margin-left:20"> <pre id="fixvalue">All DOQ header data and image file sizes are validated by Tape Validation System (TVS) software prior to archiving in the Sales Data Base. This validation procedure assures correct physical format and field values for header record elements. Logical relationships between header record elements are tested.</pre> </div><br></li> </ol><a href="#Top">Back to Top</a><hr><a name="getacopy"><h3>How can someone get a copy of the data set?</h3></a><div style="margin-left:20"><a name="getacopy.0"><b>Are there legal restrictions on access or use of the data?</b></a><br><br><div style="margin-left:20"><i>Access constraints: </i>None. No restrictions or legal prerequisites for accessing the data. The data is in the public domain and may be redistributed.</div> <div style="margin-left:20"><i>Use constraints: </i></div> <div style="margin-left:60"> <pre id="fixvalue">None. No restrictions or legal prerequisites for using the data after access is granted. The data is suitable for use at appropriate scale, and is not intended for maps printed at scales greater or more detailed than 1:12,000 scale (1 inch = 1,000 feet). Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the CT DEP and the USGS as the source for this information. For example, include the following data source description when printing this information on a map: 1990 Orthophotos - From USGS DOQQ. Source map scale is 1:12,000. Acknowledgement of the U.S. Geological Survey is appreciated in products derived from these data.</pre> </div><br></div><a name="Distrib1"></a><div style="margin-left:20"><b>Distributor 1</b> of 1</div><br><ol> <div style="margin-left:20"> <li><a name="getacopy.1"><b>Who distributes the data set?</b></a><br><br><div style="margin-left:20"> <div>State of Connecticut, Department of Enviromental Protection</div><div><pre id="fixvalue">79 Elm Street</pre></div> <div>Hartford, Connecticut 06106-5127</div> <div>USA</div><br><div>860-424-3540 (voice)</div><div>860-424-4058 (FAX)</div><div>dep.gisdata@po.state.ct.us </div><div><i>Hours of Service: </i>Monday to Friday, 08:30 to 16:30 Eastern Standard Time</div></div><br></li> <li><a name="getacopy.2"><b>What's the catalog number I need to order this data set?</b></a><br><br><div style="margin-left:20">Connecticut 1990 Orthophoto</div><br></li> <li><a name="getacopy.3"><b>What legal disclaimers am I supposed to read?</b></a><br><br><div style="margin-left:20"> <pre id="fixvalue">Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata.</pre> </div><br></li> <li><a name="getacopy.4"><b>How can I download or order the data?</b></a><br><br><ul> <li><b>Availability in digital form:</b></li><br><br><div style="margin-left:20"> <table style="border-collapse:collapse;"> <tbody> <tr> <th style="font-size: 9pt; border: solid 1px #A9A9A9; padding:4px; vertical-align:top; text-align:left;">Data format:</th> <td style="font-size: 9pt; border: solid 1px #A9A9A9; padding:4px; vertical-align:top;"> <div>ArcSDE Raster Dataset in format ArcSDE Export (version 9.1)</div> </td> </tr> <tr> <th style="font-size: 9pt; border: solid 1px #A9A9A9; padding:4px; vertical-align:top; text-align:left;">Media you can order:</th> <td style="font-size: 9pt; border: solid 1px #A9A9A9; padding:4px; vertical-align:top;">disc</td> </tr> </tbody> </table> </div><br><li><b>Cost to order the data: </b>An offline copy of the data may be accessed without charge.</li><br><br></ul> </li> <li><a name="getacopy.5"><b>Is there some other way to get the data?</b></a><br><br><div style="margin-left:20"> <pre id="fixvalue">The data distributor does not provide custom GIS analysis or mapping services. Data is available in a standard format and may be converted to other formats, projections, coordinate systems, or selected for specific geographic regions by the party receiving the data.</pre> </div><br></li> <li><a name="getacopy.6"><b>What hardware or software do I need in order to use the data set?</b></a><br><br><div style="margin-left:20">Geographic information sytem (GIS), computer-aided drawing or other mapping software is necessary to display, view and access the information.</div><br></li> </div> </ol><a href="#Top">Back to Top</a><hr><a name="metaref"><h3>Who wrote the metadata?</h3></a><div style="margin-left:20"> Dates:<br><div style="margin-left:40"> <div><i>Last modified: </i>20090429</div></div> </div><br><div style="margin-left:20"><i>Metadata author: </i><br><div style="margin-left:20"><div style="margin-left:20"> <div>Howie Sternberg</div><div>State of Connecticut, Department of Environmental Protection</div><div><pre id="fixvalue">79 Elm Street</pre></div> <div>Hartford, Connecticut 06106-5127</div> <div>USA</div><br><div>860-424-3540 (voice)</div><div>860-424-4058 (FAX)</div><div>dep.gisdata@po.state.ct.us </div><div><i>Hours of Service: </i>Monday to Friday, 08:30 to 16:30 Eastern Standard Time</div></div> </div> </div><br><div style="margin-left:20"><i>Metadata standard: </i><br><div style="margin-left:40">FGDC Content Standards for Digital Geospatial Metadata(FGDC-STD-001-1998)</div> </div><br><div style="margin-left:20"><i>Metadata extensions used: </i><br><li style="margin-left:30"><a target="viewer" href="http://www.esri.com/metadata/esriprof80.html">http://www.esri.com/metadata/esriprof80.html</a></li> </div><br><a href="#Top">Back to Top</a><br><br></body> </html>