Summary

Description

Digital orthographic imagery datasets contain georeferenced images of the Earth's surface, collected by a sensor in which object displacement has been removed for sensor distortions and orientation, and terrain relief. Digital orthoimages have the geometric characteristics of a map, and image qualities of a photograph. (Source: Circular A-16, p. 16) The Indiana 2005 digital natural-color orthophotography was collected during March and April leaf-off conditions. Data covering Vanderburgh County were collected at 6-inch resolution. Data are delivered in county sets, consisting of 4000'x4000' uncompressed 24-bit natural color TIFF files. The MrSID files were created from these data. Adjacent flight lines overlap by a minimum of 30 percent. Imagery was collected with the Leica ADS40 digital pushbroom sensor and processed with the ISTAR system. The file naming convention is as follows: xxxxyyyyH = high resolution photos (e.g., 6-inch), where xxxx and yyyy represent the easting and northing coordinates (respectively) in state plane feet, divided by 1000, of the tile origin (the top-left pixel). 6-inch MRSID files are approximately 8 MB in size. Ownership of the data products resides with the counties. Orthophotography and ancillary data products produced through this contract are public domain data. These data represent a public version of the data set and hold no distribution restrictions - please cite the data set as "IndianaMap Framework Data" with link to www.indianamap.org.