Ontario County 30 centimeter Resolution Natural Color Orthoimagery

Metadata:


Identification_Information:
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Identification_Information:
Citation:
Citation_Information:
Originator: NYS Cyber Security
Publication_Date: Sring 2006
Title:
Ontario County 30 centimeter Resolution Natural Color Orthoimagery
Geospatial_Data_Presentation_Form: remote-sensing image
Series_Information:
Series_Name: NYS Digital Orthoimagery Program (NYSDOP)
Publication_Information:
Publisher: NYS CSCIC
Description:
Abstract:
DMC imagery was collected for Ontario County New York at 10,000 AMT to produce 30 centimeter resolution Natural Color digital orthophotos, tiled.  Client provided DEM was used for orthophoto rectification.  A minimum of two base stations were established in the project area.  Image horizontal accuracy is +/-4 ft. at the 95% confidence level.  Each file contains an image covering 750 meters by 750 meters on the ground.
Purpose:
This digital orthoimagery can serve a variety of purposes, from general planning to field reference for spatial analysis to a tool for revision of vector maps. It can also serve as a reference layer for GIS.
Supplemental_Information:
Digital elevation models used for orthorectification were compiled from several sources, all of which were compiled photogrammetrically.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: April 2005
Currentness_Reference:
ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Irregular
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -79.100359
East_Bounding_Coordinate: -78.586505
North_Bounding_Coordinate: 43.289339
South_Bounding_Coordinate: 43.003088
Keywords:
Theme:
Theme_Keyword_Thesaurus: Orthophoto, ortho
Theme_Keyword: Digital orthoimagery
Access_Constraints: Some imagery tiles are classified as sensitive due to their content. These sensitive imagery tiles have been reprocessed to reduce the clarity of sensitive features. Non-sensitive content on these tiles is unaltered. Only the re-processed versions of sensitive tiles are made openly available to the public. A separate procedure is available for requesting original, full resolution versions of these tiles.
Use_Constraints:
Use of original sensitive imagery, if granted, is only for the use specified in the request.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Tim Ruhren
Contact_Organization: NYS Cyber Security
Contact_Position: NYS GIS Clearinghouse
Contact_Address:
Address_Type: mailing and physical address
Address:
30 South Pearl Street
City: Albany
State_or_Province: New York
Postal_Code: 12207-3425
Country: USA
Contact_Voice_Telephone: 518-474-5212
Contact_Facsimile_Telephone: 518-473-5848
Contact_Electronic_Mail_Address: nysgis@dhses.ny.gov
Data_Set_Credit:

Native_Data_Set_Environment:
Raw DMC digital data in stereo pair equivalent.
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Data_Quality_Information:
Logical_Consistency_Report:
The dataset contains raster images or digital ortho images so the logical consistency report is not applicable. The file naming convention was
supplied by New York state and is based on the co-ordinate pair of the lower left corner of the ortho tile. When the ortho tiles were created the file
names were restricted to a numeric value representing the lower left corner of the ortho tile. 1972577675 represents a tile with the lower left
corner of 197250, 4776750. The 4 million place was left off.  These tiles were then all renamed using a batch script so that they reflected the N.Y. state standard
u_1972577675_30_02800_col_2005.tif Consistency of file naming was ensured by the batch process.
                
Completeness_Report:
The project consisted of 208 final tiles
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
+/-4 ft. at the 95% confidence level (NSSDA)
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Not applicable.
Lineage:
Process_Step:
Process_Description:
The aerial triangulation (AT) block for the Rochester NY Urban Region, consisting of 18 flightlines and 864 images with nominal 60% forward overlap and 25% sidelap was captured in one DMC flight mission.  The AT adjustment was supported by direct georeferencing data collected via the Applanix POS/AV 510 combined carrier-phase GPS + inertial measurement unit (IMU) and was performed using Z/I Imaging's ISAT (ImageStation Automatic Triangulation) software version 4.3.06. The project was referenced to the North American Datum of 1983/1996 (NAD83/96), New York State Plane Coordinates, Central Zone (3102) horizontally and to the North American Vertical Datum of 1988 (NAVD88) vertically. Units are in US Survey Feet. 
27 survey control points were included in the adjustment, giving a control point density and geometry with a high level of redundancy for a block adjustment supported by the Applanix POS/AV 510.
The initial settings for the full XYZ survey control points were at 0.5 pixel in XY and 0.8 pixel in Z.  These were stepped-down in stages of 50% until acceptable final RMS and max residual values were achieved.  Their final settings were 0.11 ft in XY and 0.18 ft in Z.  Existing DEM data is clipped into manageable files and reviewed for potential problems or needed updates.  The existing DEM is densified where needed using ImageStation Stereo Display.  Bridge aprons are added or modified to project specifications.  The DEM is modified where any significant changes in the terrain are evident.  Breaklines are added where necessary to facilitate orthoproduction.
The DMC digital imagery is color balanced and converted from the 12 bit to 8 bits per band using ImageStation Raster Utilities. The 8 bit digital imagery is rectified to produce orthophotography using ImageStation OrthoPro. A quality control review is performed on the orthophotos. They are visually inspected for horizontal accuracy, tonal balancing, smears, relief displacement, artifacts, etc. The horizontal accuracy is assessed by comparing each GPS ground control point to the same photoidentifiable X,Y coordinate on the orthophoto and by comparing edge and mosaic seamline matches between adjacent orthophotos looking for displacement. 
Once the orthophotos have passed the quality control review, seamlines are manually created between the overlapping parts of the orthophotos. These seamlines have a 15 pixel feathering swath that ensures a seamless, color balanced transition between adjacent orthophotos in the mosaic. Multiple orthophoto chips are mosaicked then clipped to final orthophoto tiles. The final mosaic tiles are in uncompressed GeoTIFF format. 
The mosaic orthophoto tiles are checked for image quality. They are individually inspected for content, misalignments along mosaic seamlines, void areas and artifacts. The remaining errors are corrected using Adobe Photoshop in an interactive editing session. Orthophoto tiles with major errors are rejected. Orthophoto tiles with major errors are reprocessed once the error source is determined.  A final LUT is applied to all mosaics to meet client-approved radiometry.
Cloud_Cover: <1%
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Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Pixel
Row_Count: 2500
Column_Count: 2500
Vertical_Count: 1
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Spatial_Reference_Information:
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Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: Universal Transverse Mercator
Universal_Transverse_Mercator:
UTM_Zone_Number: 18
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 0.999600
Longitude_of_Central_Meridian: -75.000000
Latitude_of_Projection_Origin: 0.000000
False_Easting: 500000.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: row and column
Coordinate_Representation:
Abscissa_Resolution: 0.300000
Ordinate_Resolution: 0.300000
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222
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Entity_and_Attribute_Information:
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Entity_and_Attribute_Information:
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Distribution_Information:
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Distribution_Information:
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Transfer_Size: 208
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Metadata_Reference_Information:
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Metadata_Reference_Information:
Metadata_Date: 20050928
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: NYS CSCIC
Contact_Person: Tim Ruhren
Contact_Address:
Address_Type: mailing and physical address
Address:
30 South Pearl Street
City: Albany
State_or_Province: New York
Postal_Code: 12207-3425
Country: USA
Contact_Voice_Telephone: 518-474-5212
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Profile_Name: ESRI Metadata Profile
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