Illinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of IllinoisUnpublished Materialdekalb_demraster digital datahttp://www.isgs.illinois.eduRecommended Publishing Citation:Illinois Height Modernization Program, Illinois State Geological Survey, and DeKalb County, 2002–2014, Illinois LiDAR county database: Illinois State Geological Survey http://crystal.isgs.uiuc.edu/nsdihome/webdocs/ilhmp/ (accessed September 18, 2014)
This Digital Elevation Model (DEM) data was produced all or in part from LiDAR information as of 2009. The LiDAR derived DEM covers Dekalb County, Illinois and include inland streams, rivers, lakes ponds and tidal features. These data are appropriate for use in local and regional analysis. This data set has a vertical accuracy of 6.09 centimeters RMSEz, horizontal accuracy of 1.0 meters and point spacing of 1.2 meters. Digital Elevation Models (including terrain and surface models) are raster data sets created from whole LiDAR point cloud data sets (LAS files). The LAS files are the standard LiDAR file format which contains the raw point cloud data, these data are normally classified and distinguished between points on the ground, water or elevated features such as buildings, trees, towers, bridges, etc.. These LAS files are processed into elevation models to create gridded rasters. The first returns can be used to map the top reflective surface (Digital Surface Models - DSM), these normally include open terrain areas, as well as the tops of buildings, trees, towers, and other features elevated above the bare earth. The last returns are used to map the bare-earth terrain (Digital Terrain Models - DTM), these are normally produced with irregularly-spaced points rather than the uniform grid structure of a Digital Elevation Model (DEM), Digital Terrain Models will often include breaklines to help define edges of water bodies.These acquisitions of the LiDAR data and its derivatives were made possible by a grant from the National Geodetic Survey for the National Height Modernization Program. The program is in place to enable states access to accurate, reliable heights using global positioning satellite (GPS) technology in conjunction with traditional leveling, gravity, and modern remote sensing technologies. LiDAR data and its derivatives assist in real-world uses around the state of Illinois such as; highway engineering, flood prediction, agricultural land management, mining subsidence, monitoring archaeological features, locating sinkholes and applied geologic science.
The data do not replace the need for detailed site-specific studies. The information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. The information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor.none20090401
ground condition
Unknown-88.955-88.57742.16141.621
None
Light Detection and Ranging
LiDAR
Bare Earth
Point Cloud
Digital Elevation ModelDEMElevationSurface ModelDigital Surface ModelDSMHillshade
None
US
Illinois Department of Transportation
Illinois
Dekalb CountyNone2009DeKalb County LiDAR derivatives are proprietary data that belongs to the County of DeKalb and MUST NOT be distributed without the county's consent.
ISGS information must be obtained directly from the ISGS or from an authorized distributor. Be aware that ISGS information obtained from an unauthorized third party may have been altered subsequent to original distribution, or may no longer be current. Any access to these data, Web sites, computer systems, electronic services, and electronic networks is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section.DeKalb County LiDAR derivatives are proprietary data that belongs to the County of DeKalb and MUST NOT be distributed without the county's consent.
ISGS information is the property of and copyrighted by the Board of Trustees of the University of Illinois with all rights reserved. University copyright policy is stated in the General Rules Concerning University Organization and Procedure, Article III, Section 4. A link is provided in the Cross References section. Individuals or entities may make fair use of copyrighted ISGS material, such as reproducing a single figure or table, or using a brief text quotation, without obtaining formal permission, but in all cases the Illinois State Geological Survey must be credited as the source of the material. To reproduce ISGS information beyond the fair use standard, permission must be obtained from the ISGS Information Office, 615 East Peabody Drive, Champaign, Illinois 61820, 217-333-4747, isgs@isgs.illinois.edu. License fees and a license agreement may be required, depending on the proposed usage. Any use of these data is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section. Map information is to be used at a scientifically and cartographically appropriate scale, that is, at a scale no greater than indicated on the map or as described in the documentation of the map or map data. Map information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. Map information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor. The data do not replace the need for detailed site-specific studies.Sanborn Map Company, Illinois State Geological Survey, Illinois Department of Transportation, DeKalb CountyIllinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of Illinoismailing and physical address
615 E. Peabody
ChampaignIL61820USA217-333-4747info@isgs.illinois.eduMonday thru Friday, 8am - 5pm217-785-0211Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaignhttp://www.cam.illinois.edu/viii/VIII-1.1.htmISGS Terms of Use http://www.isgs.illinois.edu University of Illinois Web Privacy Notice http://www.vpaa.uillinois.edu/policies/web_privacy.cfm University Copyright Policy (stated in the General Rules Concerning University Organization and Procedure, Article III, Section 4) http://www.uillinois.edu/trustees/rules.cfm#sec34 Refer also to the Disclaimer of Warranties and Accuracy of Data section of the Legal Notices of Terms and Conditions section of the University of Illinois Web Privacy Policy. A link is provided in the Cross References section.All data have had QAQC visual and statistical testing using observations performed to compare the derivative products (breaklines, classified LAS, DEM and DSM/DTM) as well as aerial photography to check for the logical consistency of the data.
Complete
Lidar acquired and processed to meet 1m (RMSE) horizontal accuracy1.0 metersHorizontal point accuracy is a function of angular origination of the pulse; IMU orientation; the scanner encoder and ranging function and will vary depending on the proposed point density selected for the collection. Statistically, the error is roughly 1/3 of the illuminated foot print on the ground and is a function of the beam divergences.The vertical accuracy is based on the Sanborn independent collection of 68 FEMA checkpoints (BE, Low Veg, and HIgh veg) survey points distributed throughout the project. The fundamental vertical accuracy at 95 percent confidence level in open terrain tested 0.16 feet or 4.88 centimeters.6.09 cm RMSEzBased on the vertical accuracy testing conducted by Sanborn using NSSDA and FEMA methodology, vertical accuracy at the 95% confidence level (called Accuracyz) is computed by the formula RMSEz x 1.9600. The fundamental vertical accuracy at 95 percent confidence level ifor all classification combined tested 0.20 feet or 6.09 centimeters.The ABGPS, IMU, and raw Optech LiDAR data are integrated into the post processor software. The resultant file is in a LAS binary file format. The LAS file version 1.1 formats can be easily transferred from one file format to another. It is a binary file format that maintains information specific to the LiDAR data (return#, intensity value, xyz, etc.). The resultant points are produced in the geodetic coordinates referenced to the NAD83 horizontal datum and GRS80 vertical datum. The date and time for each flight line can be determined using the Julian date and time. The Julian date is a continuous count of days and fractions since noon Universal Time on January 1, 4713 BCE on the Julian calendar.
The unedited data are classified to facilitate the application of the appropriate feature extraction filters. A combination of proprietary filters is applied as appropriate for the production of bare earth digital terrain models (dtms). Interactive editing methods are applied to those areas where it is inappropriate or impossible to use the feature extraction filters, based upon the design criteria and/or limitations of the relevant filters. These same feature extraction filters are used to produce elevation height surfaces. The LiDAR mass points were delivered in American Society for Photogrammetry and Remote Sensing LAS 1.1 format. The header file for each dataset is complete as define by the LAS 1.1 specification. In addition the following fields are included: Flight Date Julian, Year, and Class. The LAS files do not include overlap. The data was classified as follows: Class 1 = Unclassified. This class includes vegetation, buildings, noise etc. Class 2 = Ground; Class 7 = Low Points; Class 12 = Overlap.
ISGS Secondary Processing:
1. Thorough QAQC check was completed to ensure and evaluate the quality of the data delivered and that all the specifications have been met in accordance to the contract and national specifications set for LiDAR data.
2. Through ArcGIS 10.1 the following steps were completed to created Terrain and hillshade products:
a. LAS to Mulitpoint conversion using 3D analyst tools.ASPRS Classifications were used below:
1-Unclassified
2-Ground
3-Low Vegetation
4-Medium Vegetation
5-High Vegetation
6-Building
8-Model Key Points
9-Water
b. Terrains are then created and pyramids are calculated.
c. Terrain to Raster tool was used in 3D Analyst. The parameters of data type float, natural neighbors method, sampling distance is cell size and the point spaceing value from the LiDAR data.
d. Hillshades are created from the above rasters with a Z value of 2.
3. These derivatives were checked again visually for errors. If any errors were perceived corrections were coordinated with vendor and products were updated with corrections.
4. When product was finalized then metadata was completed before making data available.20090401UnknownRastercoordinate pair0.0010.001survey feetNorth American Datum of 1983Geodetic Reference System 806378137.000000298.25722210088NAD_1983_Transverse_MercatorNorth American Vertical Datum of 19880.01survey feetExplicit elevation coordinate included with horizontal coordinates20140923Illinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of Illinoismailing and physical address
615 East Peabody Drive
ChampaignIL61820US217-333-4747isgs@isgs.illinois.eduMonday through Friday 8:00 AM to 5:00 PM (Central Time)
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
The access constraints as stated for the data apply also to the metadata. Refer to the Access Constraints section of the Identification Information section.The use constraints as stated for the data apply also to the metadata. Refer to the Use Constraints section of the Identification Information section.2013030112273000FGDC CSDGM MetadataFALSEfile://\\ISGS-VOLCANO\lidarproducts\counties\dekalb\dekalb_demLocal Area Networkdekalb_dem002818178.370025915057.3700251807731.0899471998882.0899471ProjectedGCS_North_American_1983Linear Unit: Foot_US (0.304801)NAD_1983_Transverse_Mercator<ProjectedCoordinateSystem xsi:type='typens:ProjectedCoordinateSystem' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xmlns:xs='http://www.w3.org/2001/XMLSchema' xmlns:typens='http://www.esri.com/schemas/ArcGIS/10.1'><WKT>PROJCS["NAD_1983_Transverse_Mercator",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["Transverse_Mercator"],PARAMETER["False_Easting",984250.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-88.33333333333333],PARAMETER["Scale_Factor",0.999975],PARAMETER["Latitude_Of_Origin",36.66666666666666],UNIT["Foot_US",0.3048006096012192]],VERTCS["NAVD_1988",VDATUM["North_American_Vertical_Datum_1988"],PARAMETER["Vertical_Shift",0.0],PARAMETER["Direction",1.0],UNIT["Meter",1.0],AUTHORITY["EPSG",5703]]</WKT><XOrigin>-17463800</XOrigin><YOrigin>-46132600</YOrigin><XYScale>137244822.07846552</XYScale><ZOrigin>-100000</ZOrigin><ZScale>10000</ZScale><MOrigin>-100000</MOrigin><MScale>10000</MScale><XYTolerance>0.0032808333333333331</XYTolerance><ZTolerance>0.001</ZTolerance><MTolerance>0.001</MTolerance><HighPrecision>true</HighPrecision><VCSWKID>5703</VCSWKID><LatestVCSWKID>5703</LatestVCSWKID></ProjectedCoordinateSystem>32FALSENone1GRIDTRUEcontinuousfloating point-3.4028235e+0382014091011551700201604051239320015000000050001.0FGDCIllinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of Illinoismailing and physical address
615 East Peabody Drive
ChampaignIL61820USA217-244-2414isgs@isgs.illinois.eduDeKalb County LiDAR derivatives are proprietary data that belongs to the County of DeKalb and MUST NOT be distributed without the county's consent.
Refer to the Legal Notices of Terms and Conditions of the University of Illinois Web Privacy Policy (there is a link in the Cross References section) for policy statements regarding the following:
Disclaimer of Liability
Disclaimer of Warranties and Accuracy of Data
Disclaimer of Endorsement
Disclaimer for External Links
Disclaimer of Duty to Continue Provision of Data
Security
Choice of Law
By obtaining these data you agree to the provisions of the University of Illinois Web Privacy Policy, regardless of the manner in which the information was obtained.otherno compression appliedhttp://www.isgs.uiuc.edu/nsdihome/webdocs/ilhmp/http://www.isgs.uiuc.edu/nsdihome/webdocs/ilhmp/Windows 7CD-ROMnoneno feesThe data are intended for use with GIS software. The ISGS uses ESRI ArcGIS software, however, ESRI formats can be imported into many different GIS software packages. It is expected that customers who obtain these data have the technical expertise to use GIS software. The ISGS does not provide software support of any kind.GRIDRasterISGSRaster Grid ValuesRaster Grid ValuesISGSMicrosoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.2.1.3497IL_DeKalb_DEM_2009Recommended Publishing Citation:
Illinois Height Modernization Program, Dekalb County, Illinois State Geological Survey, and Illinois Department of Transportation, 2002–2016, Illinois Height Modernization Program (ILHMP): LiDAR data: Illinois State Geological Survey http://clearinghouse.isgs.illinois.edu/ (accessed March 30, 2016)
1-88.945778-88.58643142.15419141.628302These acquisitions of the LiDAR data and its derivatives were made possible by a grant from the National Geodetic Survey for the National Height Modernization Program. The program is in place to enable states access to accurate, reliable heights using global positioning satellite (GPS) technology in conjunction with traditional leveling, gravity, and modern remote sensing technologies. LiDAR data and its derivatives assist in real-world uses around the state of Illinois such as; highway engineering, flood prediction, agricultural land management, mining subsidence, monitoring archaeological features, locating sinkholes and applied geologic science.
The data do not replace the need for detailed site-specific studies. The information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. The information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor.<DIV STYLE="text-align:Left;"><DIV><P><SPAN>This Digital Elevation Model (DEM) data was produced all or in part from LiDAR information as of 2009. The LiDAR derived DEM covers Dekalb County, Illinois and include inland streams, rivers, lakes ponds and tidal features. These data are appropriate for use in local and regional analysis. This data set has a vertical accuracy of 6.09 centimeters RMSEz, horizontal accuracy of 1.0 meters and point spacing of 1.2 meters. Digital Elevation Models (including terrain and surface models) are raster data sets created from whole LiDAR point cloud data sets (LAS files). The LAS files are the standard LiDAR file format which contains the raw point cloud data, these data are normally classified and distinguished between points on the ground, water or elevated features such as buildings, trees, towers, bridges, etc.. These LAS files are processed into elevation models to create gridded rasters. The first returns can be used to map the top reflective surface (Digital Surface Models - DSM), these normally include open terrain areas, as well as the tops of buildings, trees, towers, and other features elevated above the bare earth. The last returns are used to map the bare-earth terrain (Digital Terrain Models - DTM), these are normally produced with irregularly-spaced points rather than the uniform grid structure of a Digital Elevation Model (DEM), Digital Terrain Models will often include breaklines to help define edges of water bodies.</SPAN></P></DIV></DIV>Sanborn Map Company, Illinois State Geological Survey, Illinois Department of Transportation, DeKalb CountyLight Detection and RangingLiDARBare EarthPoint CloudDigital Elevation ModelDEMElevationSurface ModelDigital Surface ModelDSMHillshade<DIV STYLE="text-align:Left;"><DIV><P><SPAN>DeKalb County LiDAR derivatives are proprietary data that belongs to the County of DeKalb and MUST NOT be distributed without the county's consent. ISGS information is the property of and copyrighted by the Board of Trustees of the University of Illinois with all rights reserved. University copyright policy is stated in the General Rules Concerning University Organization and Procedure, Article III, Section 4. A link is provided in the Cross References section. Individuals or entities may make fair use of copyrighted ISGS material, such as reproducing a single figure or table, or using a brief text quotation, without obtaining formal permission, but in all cases the Illinois State Geological Survey must be credited as the source of the material. To reproduce ISGS information beyond the fair use standard, permission must be obtained from the ISGS Information Office, 615 East Peabody Drive, Champaign, Illinois 61820, 217-333-4747, isgs@isgs.illinois.edu. License fees and a license agreement may be required, depending on the proposed usage. Any use of these data is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section. Map information is to be used at a scientifically and cartographically appropriate scale, that is, at a scale no greater than indicated on the map or as described in the documentation of the map or map data. Map information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. Map information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor. The data do not replace the need for detailed site-specific studies.</SPAN></P></DIV></DIV>Raster Datasetdataset210818178.370025 1807731.089947818178.370025 1998882.089947915057.370025 1998882.089947915057.370025 1807731.089947866617.870025 1903306.589947322933.000000637173.000000dekalb_dem990.502136475.4201053220160405