This dataset, produced by the PAMAP Program, consists of an orthorectified digital raster image (i.e. orthoimage) with a horizontal ground resolution of 1 foot. An orthoimage is a remotely sensed image that has been positionally corrected for camera lens distortion, vertical displacement, and variations in aircraft altitude and orientation. Orthoimagery combines the image characteristics of a photograph with the geometric qualities of a map. Source images were captured in natural color at a negative scale of 1:19200. PAMAP data are organized into blocks, which do not have gaps or overlaps, that represent 10,000 feet by 10,000 feet on the ground. The coordinate system for blocks in the northern half of the state is Pennsylvania State Plane North (datum:NAD83, units: feet); blocks in the southern half of the state are in Pennsylvania State Plane South. A block name is formed by concatenating the first four digits of the State Plane northing and easting defining the block's northwest corner, the State identifier "PA", and the State Plane zone designator "N" or "S" (e.g. 45001210PAS).
Montgomery County provides this data as a free and open resource.While every reasonable effort is made to ensure the accuracy and completeness of the data, Montgomery County makes no representations about the suitability of this data for any purpose. All data is provided "as is" without warranties of any kind, either express or implied, and it should not be construed or used as a legal description.