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Sublicense Agreement No. 070401 D Digital Terrain Modeling (DTM) Compilation and 2-foot Contour Generation During the DTM compilation, elevation data will be captured by photogrammetric techniques using analytical stereo plotter devices. Each stereo model will have a series of breaklines and mass points, created to accurately depict the terrain. From this information, the DTM will be triangulated and utilized for the generation of the digital orthophotography. Quality control will consist of a check of various stereo models and compiled DTM data versus the previously collected photo identification points. Quality control will consist of a systematic check of various stereo models versus the compiled DTM data. Our operators will verify horizontal and vertical positions of the collected mass points and breaklines to check mapping accuracy. From the compiled DTM, a 2 -foot contour dataset will be generated using Industry Standard Site Design software. Contour data will be interpolated from the DTM and not photogrammetrically compiled. This process provides for a highly detailed generation of the contours; however, some level of aesthetic smoothness may be lost in the final representation. Deliverables • Digital file of compiled DTM in DGN file format. • Digital file of DTM derived 2 -foot contours in DGN file format. Digital Orthophotography Production The orthophotography will be prepared with 0.25 -foot resolution, and will meet and /or exceed National Mapping Accuracy Standards. All orthophotography will be delivered in GEO_TIF and MrSID image file formats with associated World files. The images will be mosaic'd and seamless in appearance. Radiometric adjustments will be performed to balance brightness and contrast of the imagery over the entire project area. We will submit for the City's approval a resultant sample to get acceptance of the proposed final product appearance. The orthorectified .TIF files will be tiled for delivery according to an index, tiling scheme, and file naming convention provided by the City. The tiled files will be edge matched and seamless in appearance. The MrSID compression will be conducted at a minimum 20:1 ratio to create a singular file consisting of all seamless orthorectified tiles. Deliverables Detailed Summary • Orthorectified image files in GEO TIF file format • MrSID compressed and mosaic'd imagery Photo index sheet of tiled files • DVD Delivery in bound and labeled binder Project Summary • 3 Inch Imagery • 0.25' pixel (1 " =500' Photoscale with 1 " =100' Horizontal Mapping Accuracy) • 0.25' Respectively Pixel Color Orthophotography • 2 -foot DEM Derived Contours and DTM (1 " =500' Photoscale) • 225 Stereo Models • 236 Exposures • 11 Flight Lines • 8 Aerial Control Points