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2011 Wayne County Orthophotography
Dataset Basics Wayne County selected Pixxures as the acquisition vendor for their spring 2011 orthophotography project. This dataset covers all of Wayne County, including the City of Richmond. Pixxures acquired the 3-inch imagery March 19, 2011. They acquired the 6-inch imagery March 26 (southern part of county) and March 28, 2011. Pixxures used autocorrelation to create a new elevation model and exported the las files to a file geodatabase providing both edited and unedited multi-point feature classes. Pixxures collected the imagery using Leica ADS direct digital sensors, which have a 62 millimeter focal length. Collection was performed using a twin-engine aircraft flying at an average flying height of 4,800 feet above mean terrain with 30% sidelap, giving the collected data nominal ground sampling distance of 6 inches and at 2,400 feet above mean terrain for a nominal ground sampling distance of 3 inches. Based upon the CCD Array configuration present in the ADS40 digital sensor, imagery for each flight line is 12,000 pixels in width. NIR, Red, Green, Blue, and Panchromatic image bands were collected for each resolution. Pixxures compiled the orthophotos to meet NMAS 1"=100' accuracy standards. A new surface model was autocorrelated from the newly collected imagery utilizing all bands enabling multiple views of surface features. The surface model was edited to remove above ground points and to interpret new points in areas of heavy vegetation and buildings. The resulting DTM was then gridded to an even spacing for orthorectification. The Wayne County GIS Website provides online interactive viewing of the imagery. File Formats Each image is archived in a .zip file which includes the image and any ancillary files. Tiled Images File Type: tiled (block size 256x256), uncompressed, geotiff County and Regional Mosaic Images File Format: ECW compressed Target Compression Ratios: Richmond 1:18; Wayne County 1:24; All Others: 1:1
Elevation Countywide personal geodatabase with edited and unedited elevation point datasets DataSet Contact Shaun Scholer, GIS Manager for the City of Richmond/Wayne County GIS Interlocal
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