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Top precision aerial mapping camera and fine-grain aerial negative film, or possibly a <br />digital aerial camera. <br />Photo Lab Work <br />This task involves processing of the aerial negative film, and production of derivative hard- <br />copy products. <br />• The aerial negatives will be processed, labeled, and checked for compliance with the <br />City-approved flight plan and industry standard flight tolerances. <br />• Contact prints will be printed using a LogETronics Mark 11 Automatic Dodging <br />Printer, and processed using an AGFA Model 125 Automatic Processor. <br />Film Scanning <br />This task involves scanning of the aerial negatives to produce raw digital raster imagery in <br />preparation for analytical aerotriangulation, photogrammetric data extraction and <br />orthorectification. <br />• Negatives of the aerial photography will be placed into a precision Photogrammetric <br />Scanning System and scanned at a resolution of 12.5 microns (2032 DPI). <br />• Automatic dodging software will optimize each image, evening out localized bright <br />and dark patches to ensure even, consistent looking imagery of the highest possible <br />quality for imaging tasks. <br />Analytical Aerotriangulation <br />This task involves the densification and verification of field control data in order to enable <br />the aerial imagery to be used for photogrammetric processes. <br />• All point marking and reading will be performed digitally. All targeted ground <br />control, passpoints, checkpoints and drop points will be located, symbolized and <br />marked digitally on the raster images. <br />• Analytical aerotriangulation computations will be run using ORIMA software, which <br />is capable of performing block/bundle adjustments using a rigorous least squares <br />analysis, and possesses error detection and removal facilities. Corrections for lens <br />distortion, earth curvature, atmospheric refraction, and film shrinkage will be applied. <br />• The output X, Y and Z residuals for all control points and RMS errors for the entire <br />control network will be examined to ensure that they fall within the acceptable range <br />for the accuracy level of mapping selected by the City. <br />Digital Terrain Model Creation <br />This task involves creation of digital terrain models to support generation of contours and <br />production of digital orthophotos. <br />• Masspoints and breaklines will be extracted in the quantities and locations needed to <br />12