DIGITAL MAP PRODUCTS -2007 - Laserfiche WebLink

Home Browse Search

Sublicense Agreement No. 070401 D Exhibit F Agreement 070401 D SERVICES SPECIFICATIONS ORTHOPHOTOGRAPHY Project Scope The scope of this project is to provide 0.25 -foot pixel resolution color digital Ortho - photography for the City of Santa Ana. In addition to the Ortho - photography a Digital Terrain Model (DTM) and DTM generated 2 -foot contours will be produced and provided as a digital deliverable. The project limits will be based upon the City's boundary plus a buffer as outlined in attached image file in Exhibit G. Project Approach Ground Control and Airborne GPS Procedures We propose to establish (8) eight ground control points that will be constrained and adjusted in relationship with the High Precision Geodetic Network to meet Second Order control specifications, or better. In order to reduce the number of ground control points, we propose to use airborne GPS to supplement the surveyed ground control. GPS field crews will conduct observations in accordance with the guidelines set forth in the draft Federal Geodetic Control Committee (FGCC) "Geometric Geodetic Survey Standards and Specifications for Geodetic Surveys using GPS Relative Positioning Techniques," version 5.0, dated May 1988, reprinted with corrections August 1, 1989. All surveying will be performed under the direction of a licensed land surveyor in California. All surveys will be completed using dual - frequency GPS receivers. Static survey techniques and fieldwork will be documented with field observation sheets to be filed with the project survey files. The observed data will be checked for completeness, accuracy, and conformance to project specifications. We will use an airborne GPS system designed for direct geo- referencing of aerial photography. GPS technology and post - processing software within this system measures the absolute position (X, Y, Z) and rotation elements (omega, kappa, phi) of each photograph. The system also measures the position of the camera perspective center and orientation angles of each photograph at the exact time of exposure. We propose to combine these results with the ground survey points and provide a rigorous bundle adjustment before the start of compilation. GPS Survey Adjustments Upon completion of all GPS observations and baseline post - processing, a comprehensive least squares network adjustment will be made of the entire control network using GeoLab least squares software. The datum for horizontal adjustments and positions will be the North American Datum of 1983 (NAD 83). The datum for vertical adjustments and elevations will be the North American Vertical Datum of 1988 (NAVD 88). All horizontal values will be published in the California Coordinate System 1983 (CCS83), Zone 6, State Plane values in U.S. Survey Feet. Deliverables • Proposed ground control layout and flight map • Complete digital listing of all control station coordinates