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Sensor Positional Accuracy: 15 cm absolute Sensor Directional Accuracy: 0.01 degrees absolute We utilize a Litton IMU (Inertial Measurement Unit - utilized in cruise missiles), a ground station post-corrected GPS, and Kalman filtering to achieve the high degree of positional and directional accuracy. Ortho-rectification: Geo-referenced square pixels The images will be ortho-rectified to back out the optical deviations of the capture system and then resampled, utilizing USGS DEM data (30-meter postings or better if available from county), to produce square pixels on the ground. Raw digital images will be available for customers who wish to resample with higher resolution elevation data. Orthogonal Stereo Pairs: 67% overlap along flight line (2680 feet) 22% overlap between flight lines (1320 feet) Each sector will contain a stereo pair that fills the sector, plus the overlap from the adjacent sectors. Image Export: JFIF (JPEG), TIFF, MrS1D, GIF With associated geography file for import into GIS The proprietary image format can be directly read into GIS packages that can import JFIF files or the file can be converted to any of the above image formats. An associated geography mapping file will be delivered with each orthogonal image for direct import into GIS. Geo-data Export: delineated text files Currently, geo-data may be exported as points or lines to a delineated text file for import into G1S. The data may be pulled into GIS packages through a relatively simple process. Future releases will include a means to export directly to a GIS recognized geography file format. Image Tiling and Terrain Profiles: We do not tile the orthogonal images, nor pull terrain profiles out of the stereo pairs. However, our orthogonal images are in a form that can be pulled into existing applications that can perform both these functions. Notes: As of this date, the existing National Map Accuracy Standards apply primarily to conventional analog aerial photography products in hard copy form. Research is currently underway by the major manufacturers of precision digital aerial mapping can~eras to achieve the existing specifications and to be able to produce mapping to National Map Accuracy Standards. It should be noted that many of the applications identified by county agencies do not require high levels of accuracy and those that do require it can be achieved through the use of third party software packages such as the ERDAS Imagine Orthobase product which allows orthophoto images to be rectified to existing monumentation and ground control data. We recommend that these improvements be undertaken on a project- specific basis rather than on a countywide level, given the expense involved. Page 2 of 2 0201