2011 Hamilton County Orthophotography

Dataset Basics

The Hamilton County 2011 digital natural-color orthophotography was collected on March 28 during leaf-off conditions at a resolution of 6-inch resolution. The data cover the entire land area of Hamilton County, Indiana, or 434 square miles. Data are delivered tiles, consisting of 2500'x 2500' uncompressed 24-bit natural color TIFF files.  Accuracy is +/- 2.50 feet. The entire perimeter of the county is buffered by at least 2,000 feet. Adjacent flight lines overlap by a minimum of 30 percent.  Imagery was collected with the Z/I Imaging DMC digital sensor.  The file naming convention is as follows: xxxyyyy where xxx and yyyy represent the easting and northing coordinates (respectively) in state plane feet, divided by 1000, of the tile origin (the bottom-left pixel).  TIFF files are approximately 75 MB in size.  Ownership of the data products resides with Hamilton County.

Available Datasets

2011 Hamilton County Orthophotography (GeoTIFF)

Imagery from the 2011 orthoimagery project conducted by Hamilton County.

2011 Hamilton County Orthophotography (JPG)

Imagery from the 2011 orthophotography project for Hamilton County in JPG format.

File Format

Data_Quality_Information:

  • Attribute_Accuracy:
  • Attribute_Accuracy_Report:
      • The digital orthophotos were evaluated by The Sidwell Company to ensure each tile extent was 2500 feet x 2500 feet in Eastings and Northings for the appropriate Indiana State Plane coordinate system, that the world file references the center of the pixel located in the upper left hand corner of the tile as the point of origin, that the ground sample distance (GSD) is 6-inches.
  • Logical_Consistency_Report:
    • Compliance with the accuracy standard was ensured by comparison with previously acquired orthophotography and planimetric data.
  • Completeness_Report:
    • The following methods are used to assure imagery accuracy.
      • 1. Use of IMU and ground control network utilizing GPS techniques.
      • 2. Use of airborne GPS in conjunction with the acquisition of imagery.
  • Positional_Accuracy:
    • Horizontal_Positional_Accuracy:
    • Horizontal_Positional_Accuracy_Report:
      • The orthophotos were compiled to meet 2.5 feet horizontal accuracy at 95% confidence level.
  • Direct_Spatial_Reference_Method: Raster
    • Raster_Object_Information:
    • Raster_Object_Type: Pixel
  • Spatial_Reference_Information:
    • Horizontal_Coordinate_System_Definition:
    • Planar:
      • Grid_Coordinate_System:
        • Grid_Coordinate_System_Name: State Plane Coordinate System 1983
      • State_Plane_Coordinate_System:
        • SPCS_Zone_Identifier: 1301
        • Transverse_Mercator:
      • Scale_Factor_at_Central_Meridian: .9999666667
      • Longitude_of_Central_Meridian: -037.300000
      • Latitude_of_Projection_Origin: +85.400000
      • False_Easting: 100000.00
      • False_Northing: 250000.00
    • Planar_Coordinate_Information:
      • Planar_Coordinate_Encoding_Method: coordinate pair
    • Coordinate_Representation:
      • Abscissa_Resolution: 1.0 and .5
      • Ordinate_Resolution: 1.0 and .5
    • Planar_Distance_Units: Survey Feet
    • Horizontal_Datum_Name: North American Datum of 1983,1986 Adjustment