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This task involves orthorectification of the raw digital raster images that were created by scanning the aerial negatives. A number of image processing techniques are used to maximize the quality of the deliverable images. The unrectified raster images will be georeferenced to the DTM's using the field control, analytical aerotriangulation and aerial camera data. The digital orthophotography will be created by draping the unrectified raster images over their corresponding digital terrain models. All relief displacement will be removed from the raw image files at ground level on a pixel-by-pixel basis, yielding a set of orthorectified digital photo images. Mosaicking will be performed to ensure a perfect edge match between all orthophoto sheet tiles. Creation of seam lines is performed interactively to ensure that no image flaws result from seam lines passing through tall structures. Radiometric adjustment will be performed to balance and match color tones, brightness and contrast of the imagery over the whole project. Histograms will be applied on a project basis and not just to adjacent tiles, ensuring uniformity of tone over the entire 51 50 E. Hunter Ave. 9 Anaheim, CA 92807 (71 4) 777-8877 alanfrank@johnson-frank.com FAX: (714) 777-1641 Johnson-Frank & Associates, Inc. On-Call Aerial Mapping & Surveying Services City of Santa Ana image database. Image editing software will be used to repair any minor flaws on the imagery. The imagery will be tiled into sheets as desired by the City. The digital orthophoto software will be instructed to output a .COT file for each orthophoto tile. The completed image data set will be written to CD-ROM disks for delivery to the City. Images will be delivered in the format selected by the City, including .ecw files if requested. Ground /Field Topographic Suweys This task involves the survey and data collection of any features to be picked up by crews in the field. Prior to submitting a cost estimate, we always thoroughly review the survey request as well as the site at hand, both from on-site visits as well as through aerial and satellite imagery readily available through Google Earth. Our project manager will attend pre-project meetings with the City's staff or other City consultants as may be needed. We will adhere to the City control system, if any, and provide control deliverables in digital format. We will adhere to the City's line and symbology requirements as they may pertain to CAD files. This is an issue with which we are very familiar. Working with local municipalities, Counties, and US Governmental agencies, we are familiar with translating into anyone's CAD standards seamlessly. All of our topographic work products are produced, and will be delivered in Microstation (or AutoCAD if requested). In addition, we will submit ASCII coordinate files along 21 25K-23