2001 Digital Orthophotography

In 2001, the North Central Texas Council of Governments facilitated the purchase of digital aerial photography (orthos) for the following 11 counties in North Central Texas: Collin, Dallas, Denton, Ellis, Hunt, Johnson, Kaufman, Navarro, Rockwall, Somervell and Tarrant.

The contractor for this project was Vargis, LLC.  The orthos  were collected from February to March of 2001 and lower resolution imagery  are available for purchase via the DFWmaps Marketplace according to the following price schedule.


Georeferenced TIFF images are sold in  3,000' x 2,000' tiles, or 0.215 square miles. Sample images and a shapefile of the tile structure may be downloaded below:

2-Foot Resolution Color Ortho Sample [TIFF format with world file; 3.8 MB]

TIFF orthophotography grid - ShapefileDXF file

Specifications

The digital orthophotography was produced using accepted photogrammetric industry practices under the supervision of Certified Photogrammetrists and Licensed Surveyors. Digital orthophoto products are guaranteed to meet National Map Accuracy Standards at a map scale of 1"=200' (1:2,400). Photo scale is 1"=1,500' (1:18,000). Products are mosaicked and color balanced to create a near seamless appearance. Sample products are available for evaluation of image quality and positional accuracy.

Sensor Type Aerial film camera with 6" focal length
Negative Size 9" x 9"
Altitude of Capture 9,000' above mean terrain
Capture Period February-March 2001
Control Sources Ground survey and airborne GPS
Scanning Resolution 15 microns
Ground Resolution 1.0 US Survey Foot
Color Type 24-bit Natural Color
Coordinate System Texas State Plane, North Central Zone
Horizontal Datum NAD 83
Units US Survey Feet
Format TIFF or MrSID (1 MrSID tile = 120 TIFF tiles)


View the Metadata for for more information on the 2001 orthophotography project.

For additional questions about the 2001 orthophotography, visit the SDCP FAQ page or contact Shelley Broyles.