AerialPhotography2008 (ImageServer)

View In: ArcGIS JavaScript ArcGIS Online Map Viewer ArcGIS Earth ArcMap

View Footprint In: ArcGIS Online Map Viewer

Service Description: Aerial AcquisitionFugro Earthdata, Inc. acquired the aerial imagery from April 10-18, 2008, flying north-south to support the creation of digital orthophotography with a 15cm pixel (Boston Upgrade areas) and a 30cm pixel (entire Boston UA133 region). The 15cm imagery was acquired in seven flights, at approximately 4,800 feet above mean terrain (AMT). There were 120 flight lines. The 30cm imagery was acquired in six flights, at approximately 9,440 feet AMT. There were 52 flight lines. All imagery was collected using a Leica ADS40 digital pushbroom sensor. Source imagery was cloud-free. Photography was flown during leaf-off in deciduous vegetation regions. In downtown Boston a "true ortho" method was used to reduce the effects of tall building lean.The aerial photography used to create the 2009 digital images was acquired by Fugro Earthdata, Inc. between March 24 to April 26, 2009. The orthophotography was created for use by the USGS, The National Geospatial-Intelligence Agency, and MassGIS. There were eleven sorties and 225 flight lines. All imagery was collected using the Leica ADS40-52 digital pushbroom sensor.Orthorectification For both years' imagery, Fugro EarthData used ISTAR to process a digital surface model (DSM) for orthorectification of the imagery. ISTAR digital surface modeling is based on an auto correlated pixel-matching system within the ISTAR software. The auto correlated DSM surface represents the initial surface model. The following is the process used:Using the DSM, a technician performed a visual inspection of the data to verify that the flight lines met correctly. The technician also verified that there were no voids, and that the data covered the project limits. The technician then selected a series of areas from the dataset and inspected them where adjacent flight lines met. This DSM surface is used in the rectification of the orthoimagery. Ground ControlDewberry and Davis LLC was contracted by the USGS to acquire photo identifiable ground control points (50 in 2008 and 109 in 2009) during the acquisition of aerial imagery. The ground control points were established using GPS for vertical (NAVD 88 Meters) and horizontal (NAD83(NSRS2007) coordinate values (UTM Zone 19N in 2008, Massachusetts Stateplane Mainland US Survey Meters in 2009). Spatial Data Quality - Horizontal Positional AccuracyThe 15cm orthophotos were created to be fully compliant with a horizontal positional accuracy not to exceed 0.6 meters Root Mean Squared Error (RMSE). Error XY does not exceed 0.424 meter RMSE in X or Y. The 30cm orthophotos were created to be fully compliant with a horizontal positional accuracy not to exceed 3 meters RMSE. Error XY does not exceed 2.12 meter RMSE in X or Y. Detailed accuracy reports were delivered to MassGIS.Twenty-one points acquired by the MassHighway Survey Section were used to test the horizontal accuracy of the 15cm imagery. The surveyed coordinates were compared with coordinate values read for the corresponding image in the ortho product. The diagonal RMSE (XY) was 0.21m (NSSDA statistic was 0.36m). This fell within the 0.6m tolerance defined in the Statement of Work.Forty-nine points also acquired by the MassHighway Survey Section were used to test the horizontal accuracy of the 30cm imagery. The surveyed coordinates for the points were compared with coordinate values read for the corresponding image in the ortho product. The diagonal RMSE (XY) was 0.44m (NSSDA statistic was 0.75m). This fell well within the 3.0m tolerance defined in the Statement of Work. ProcessingProcessing by Fugro Earthdata included radiometric adjustments made using Earthdata proprietary tools and mosaicking the ADS40 imagery strips. QA/QC was performed to ensure that the mosaic lines were appropriately placed and that there was appropriate imagery coverage. Technicians also looked for anomalies, smears and other indications of problems within the digital orthophoto creation process. Where necessary, tonal balancing was performed over a group of images during the mosaicking process which served to lighten or darken adjacent images for better color tone matching. Two additional radiometric adjustments were applied to the completed orthos in Adobe Photoshop, including a sharpening mask filter, used to help increase sharpness of a digital image.The final digital ortho product delivered to MassGIS was a set of GeoTIFF files in the UTM Zone 19N (in 2008) and NAD83(NSRS2007) Massachusetts Stateplane Mainland meters (in 2009) coordinate systems. Images were non-overlapping tiles covering a 1,500-meter by 1,500-meter block on the ground. As requested by the Mass. Executive Office of Public Safety, MassGIS "deresolved" the imagery in a few areas for security reasons. Using ArcGIS Desktop 9.2, MassGIS then merged the 2008 UTM files into large blocks and projected the data into the Massachusetts State Plane Mainland NAD83 Meters coordinate system. The projection process resulted in a slight offset of large bands of pixels, most noticeable in linear features (like tennis court lines) when viewed at close scales. Tiles were clipped out into new 1,500-meter by 1,500-meter blocks; each image name is based on the first four digits of the X and Y coordinates of the center of the tile in NAD83 Mass. State Plane meters. MassGIS' quality assurance included extensive visual examination for errors, anomalies, spatial accuracy and completeness of the imagery. Because the 2009 30cm imagery was delivered in the NAD83(NSRS2007) Massachusetts Stateplane Mainland coordinate system, the mosaic-and-clip methodology used on the 2008 data was not required. However, the NSRS2007 adjustment to the NAD83 coordinate system was not supported by most GIS software, so MassGIS simply "redefined" the spatial reference of each image to the earlier Massachusetts State Plane Mainland NAD83 Meters coordinate system. This final step did not shift the images or result in any loss of horizontal accuracy. The 2009 15cm imagery was delivered to MassGIS in the Mass. State Plane Feet coodinate system at 6-inch pixel resolution. These image tiles were merged into a single file geodatabase raster dataset, projected to Mass. State Plane Meters at 15cm resolution, and clipped out according to the 2008/2009 ortho index.

Name: AerialPhotography2008

Description: Aerial AcquisitionFugro Earthdata, Inc. acquired the aerial imagery from April 10-18, 2008, flying north-south to support the creation of digital orthophotography with a 15cm pixel (Boston Upgrade areas) and a 30cm pixel (entire Boston UA133 region). The 15cm imagery was acquired in seven flights, at approximately 4,800 feet above mean terrain (AMT). There were 120 flight lines. The 30cm imagery was acquired in six flights, at approximately 9,440 feet AMT. There were 52 flight lines. All imagery was collected using a Leica ADS40 digital pushbroom sensor. Source imagery was cloud-free. Photography was flown during leaf-off in deciduous vegetation regions. In downtown Boston a "true ortho" method was used to reduce the effects of tall building lean.The aerial photography used to create the 2009 digital images was acquired by Fugro Earthdata, Inc. between March 24 to April 26, 2009. The orthophotography was created for use by the USGS, The National Geospatial-Intelligence Agency, and MassGIS. There were eleven sorties and 225 flight lines. All imagery was collected using the Leica ADS40-52 digital pushbroom sensor.Orthorectification For both years' imagery, Fugro EarthData used ISTAR to process a digital surface model (DSM) for orthorectification of the imagery. ISTAR digital surface modeling is based on an auto correlated pixel-matching system within the ISTAR software. The auto correlated DSM surface represents the initial surface model. The following is the process used:Using the DSM, a technician performed a visual inspection of the data to verify that the flight lines met correctly. The technician also verified that there were no voids, and that the data covered the project limits. The technician then selected a series of areas from the dataset and inspected them where adjacent flight lines met. This DSM surface is used in the rectification of the orthoimagery. Ground ControlDewberry and Davis LLC was contracted by the USGS to acquire photo identifiable ground control points (50 in 2008 and 109 in 2009) during the acquisition of aerial imagery. The ground control points were established using GPS for vertical (NAVD 88 Meters) and horizontal (NAD83(NSRS2007) coordinate values (UTM Zone 19N in 2008, Massachusetts Stateplane Mainland US Survey Meters in 2009). Spatial Data Quality - Horizontal Positional AccuracyThe 15cm orthophotos were created to be fully compliant with a horizontal positional accuracy not to exceed 0.6 meters Root Mean Squared Error (RMSE). Error XY does not exceed 0.424 meter RMSE in X or Y. The 30cm orthophotos were created to be fully compliant with a horizontal positional accuracy not to exceed 3 meters RMSE. Error XY does not exceed 2.12 meter RMSE in X or Y. Detailed accuracy reports were delivered to MassGIS.Twenty-one points acquired by the MassHighway Survey Section were used to test the horizontal accuracy of the 15cm imagery. The surveyed coordinates were compared with coordinate values read for the corresponding image in the ortho product. The diagonal RMSE (XY) was 0.21m (NSSDA statistic was 0.36m). This fell within the 0.6m tolerance defined in the Statement of Work.Forty-nine points also acquired by the MassHighway Survey Section were used to test the horizontal accuracy of the 30cm imagery. The surveyed coordinates for the points were compared with coordinate values read for the corresponding image in the ortho product. The diagonal RMSE (XY) was 0.44m (NSSDA statistic was 0.75m). This fell well within the 3.0m tolerance defined in the Statement of Work. ProcessingProcessing by Fugro Earthdata included radiometric adjustments made using Earthdata proprietary tools and mosaicking the ADS40 imagery strips. QA/QC was performed to ensure that the mosaic lines were appropriately placed and that there was appropriate imagery coverage. Technicians also looked for anomalies, smears and other indications of problems within the digital orthophoto creation process. Where necessary, tonal balancing was performed over a group of images during the mosaicking process which served to lighten or darken adjacent images for better color tone matching. Two additional radiometric adjustments were applied to the completed orthos in Adobe Photoshop, including a sharpening mask filter, used to help increase sharpness of a digital image.The final digital ortho product delivered to MassGIS was a set of GeoTIFF files in the UTM Zone 19N (in 2008) and NAD83(NSRS2007) Massachusetts Stateplane Mainland meters (in 2009) coordinate systems. Images were non-overlapping tiles covering a 1,500-meter by 1,500-meter block on the ground. As requested by the Mass. Executive Office of Public Safety, MassGIS "deresolved" the imagery in a few areas for security reasons. Using ArcGIS Desktop 9.2, MassGIS then merged the 2008 UTM files into large blocks and projected the data into the Massachusetts State Plane Mainland NAD83 Meters coordinate system. The projection process resulted in a slight offset of large bands of pixels, most noticeable in linear features (like tennis court lines) when viewed at close scales. Tiles were clipped out into new 1,500-meter by 1,500-meter blocks; each image name is based on the first four digits of the X and Y coordinates of the center of the tile in NAD83 Mass. State Plane meters. MassGIS' quality assurance included extensive visual examination for errors, anomalies, spatial accuracy and completeness of the imagery. Because the 2009 30cm imagery was delivered in the NAD83(NSRS2007) Massachusetts Stateplane Mainland coordinate system, the mosaic-and-clip methodology used on the 2008 data was not required. However, the NSRS2007 adjustment to the NAD83 coordinate system was not supported by most GIS software, so MassGIS simply "redefined" the spatial reference of each image to the earlier Massachusetts State Plane Mainland NAD83 Meters coordinate system. This final step did not shift the images or result in any loss of horizontal accuracy. The 2009 15cm imagery was delivered to MassGIS in the Mass. State Plane Feet coodinate system at 6-inch pixel resolution. These image tiles were merged into a single file geodatabase raster dataset, projected to Mass. State Plane Meters at 15cm resolution, and clipped out according to the 2008/2009 ortho index.

Single Fused Map Cache: false

Extent:

Initial Extent:

Full Extent:

Pixel Size X: 0.4921250000000049

Pixel Size Y: 0.4921249999999571

Band Count: 3

Pixel Type: U8

RasterFunction Infos: {"rasterFunctionInfos": [{ "name": "None", "description": "", "help": "" }]}

Mensuration Capabilities: Basic

Has Histograms: true

Has Colormap: false

Has Multi Dimensions : false

Rendering Rule:

Min Scale: 0

Max Scale: 0

Copyright Text: Furgo Earthdata, Inc., Dewberry and Davis, LLC, MassGIS, Harvard University, Arnold Arboretum, Brian Morgan.

Service Data Type: esriImageServiceDataTypeRGB

Min Values: 0, 0, 0

Max Values: 255, 255, 255

Mean Values: 70.04783358023275, 70.03026695834623, 51.87866729137922

Standard Deviation Values: 38.130178162539345, 35.18203568808627, 33.02127563701472

Object ID Field:

Fields: None

Default Mosaic Method: Center

Allowed Mosaic Methods:

SortField:

SortValue: null

Mosaic Operator: First

Default Compression Quality: 75

Default Resampling Method: Bilinear

Max Record Count: null

Max Image Height: 4100

Max Image Width: 15000

Max Download Image Count: null

Max Mosaic Image Count: null

Allow Raster Function: true

Allow Compute TiePoints: false

Supports Statistics: false

Supports Advanced Queries: false

Use StandardizedQueries: true

Raster Type Infos:

Has Raster Attribute Table: false

Edit Fields Info: null

Ownership Based AccessControl For Rasters: null

Child Resources: Info Histograms Key Properties Legend rasterFunctionInfos

Supported Operations: Export Image Identify Measure Compute Histograms Compute Statistics Histograms Get Samples Compute Class Statistics Query Boundary Compute Pixel Location Validate Project