These files contain 2004 digital orthoimagery of Rockland County, New York. Image pixel size is 30 cm. GSD. Image type is natural color. 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.
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.
Digital elevation models used for orthorectification were compiled from several sources, all of which were compiled photogrammetrically.
30 South Pearl Street
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. 10470162 which represented a tile with the lower left corner of 1047000, 162000. These tiles were then all renamed using a batch script so that they reflected the N.Y. state standard e_10470162_12_07200_col_2004.tif Consistency of file naming was ensured by the batch process.
The project consisted of 1222 final tiles
+/-4 ft. at the 95% confidence level (NSSDA)
The aerial film was acquired in April 2004. The imagery was scanned at 14 microns using a Z/I Imaging PhotoScan 2000 scanner. The Ground control used to support the ortho mapping was collected by either paneling and targeting of permanent monuments or photographic identification of strategic points. The coordinates were collected via ground survey techniques. The Aerial Triangulation was performed on softcopy workstations using Z/I platform software. The final bundle adjustment was performed using PAT-B software. Digital Elevation Models were provided by the client in various formats. They were merged together and duplicate data deleted where necessary. All DTM were reviewed for changes to the terrain and updated on softcopy workstations using the 2004 photography. All bridges were modeled in 3-D to properly rectify them on the imagery. They were captured using standard photogrammetric stereo-compilation techniques on softcopy workstations. Sanborn's Metro process is able to rectify bridges with the same methodology used to model all other ground features. The bridges area coded uniquely and later removed from the final DTM file. The images were ortho-rectified using METRO, Sanborn's proprietary software. Color balancing was performed using METRO_NICE software. The resulting images are seamlessly mosaiced into orthophoto tiles. Images were quality controlled using Adobe PhotoShop software. Final deliverables in geotiff format with tfw files and metadata files where placed on DVD Media.
30 South Pearl Street