These files contain 2002 digital orthoimagery of Niagara County, New York. Image pixel size is 60 cm. GSD. Image type is panchromatic. Image horizontal accuracy is +/-8 ft. at the 95% confidence level. Each file contains an image covering 1500 m. by 1500 m. 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 where compiled from several sources, all of which were compiled photogrammetrically.
Use of sensitive imagery, if granted, is only for the use specified in the request.
30 South Pearl Street
NYS Office of Cyber Security
The dataset contains raster images or digital or digital ortho images so the logical consitency 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 where 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 I_10470162_12_5000_col_2000.tif Consistency of file naming was ensured by the batch process.
The project consisted of 479 final tiles
+/-8 ft. at the 95% confidence level (NSSDA)
The aerial film was acquired in 2002. The imagery was scanned at 14 microns using a Z/I Imaging Photoscan TD-1 scanner. The Ground control used to support the ortho mapping was collected by identifying strategic points on the aerial photography then determining the coordinates by ground survey techniques. The Aerial Triangulation was performed using softcopy workstations and Intergraph's ISDM software. Bundle adjustment was performed using PAT-B and Digital Elevation Models were created using standard photogrammetric collection techniques on Intergraph's SSK soft copy workstation. During the bridging process,both the DEM and the bridge deck were captured as well as the ground features surrounding the bridge. A "DTM apron" was delineated at each side of the elevated bridge and the resulting smearing is located and accumulated in the solid black apron area. The images were then ortho rectified using Intergraph's Base Rectifier software. Color balancing was performed using both Intergraph's IRASC package and Orthovista. Seamless mosaicing was performed using Triathlon's AIM software and the seamless mosaic was clipped into tiles using Triathlon's Clipmos software. Images were then inspected using Intergraph's IRASC and Adobe PhotoShop software. Final files were then compressed using MrSID. Final deliverables in tiff format with tfw files where placed on DVD while the MrSID files were placed on CD. Final quality control for horizontal accuracy and image quality was performed by New York State.
30 South Pearl Street