New York State Office of Cyber Security
Geographic Information Systems Clearinghouse
Department
of Transportation
1:24,000 Scale Raster Quadrangles
Quadrangles produced by the NYSDOT Mapping and GIS Section are available as digital raster files. These files duplicate in digital form the map image that appears on the corresponding printed NYSDOT 1:24,000 scale quadrangle map. The files are raster images composed of pixels, and are not vectorized for use as intelligent GIS layers. However, they are well suited for use as a backdrop to other GIS layers to provide additional visual information or for on-screen, "heads-up" digitizing, as well as general display and plotting of the map image. The files may be used with a variety of UNIX and PC-based graphics, CAD, and GIS software packages.
Data Source
These files were created by scanning NYSDOT planimetric and topographic quadrangle maps. The quadrangles were originally prepared by USGS but have been thoroughly updated (except for contours) by NYSDOT as part of an ongoing revision program. Quadrangles produced since 1990 have been revised using a full digital raster-based production process.File Scan Types
The available files are the result of one of the following two production processes or scan types:- Film Scan
Quadrangles last revised prior to 1990. Scanned by DOT or contractor from a specially prepared heliofilm (film positive). Adjacent quadrangles edgematched. No obscuring hydrography or urban area screen tints. File resolution of 508 DPI. - Full Digital Process
Quadrangles revised since 1990. Scanned by DOT from a specially prepared heliofilm (film positive) and then revised using a completely digital raster production process. No obscuring hydrography or urban area screen tints. File resolution of 508 DPI.