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An orthoimage is remotely sensed image data in which displacement of features in the image caused by terrain relief and sensor orientation have been mathematically removed. Orthoimagery combines the image characteristics of a photograph with the geometric qualities of a map. This task consists of two components, digital image acquisition and digital orthophoto production, covering the Southwest Florida Water Management District in Florida. The Southwest Florida Water Management District (SWFWMD) project area is comprised of approximately 10,589 square miles. Aerial imagery was collected in panchromatic, Red, Green, Blue and Near Infrared which yielded a natural color and false color infrared version of the completed digital orthophotography. Imagery was collected at an approximate altitude of 23,600 feet above mean terrain. The ADS40 digital camera system used in this project incorporates the latest in sensor technology, optics, electronics, data transfer, and storage. The ADS40 imagery is generated from seven parallel sensor lines in the focal plane of a single lens system, three panchromatic (forward, nadir, backward), red, green, and blue lines placed next to each other, and one infrared. Each panchromatic channel consists of two lines, each with 12,000 pixels, staggered (shifted with respect to each other) by 0.5 pixels. The viewing angles and characteristics of the sensor are as follows -
Focal length 62.5mm Pixel size 6.5mm PAN 2 arrays 12,000 pixels each
R,G,B and NIR,R,G 12,000 pixels Forward to nadir stereo angle 28.3 degrees
Backward to nadir stereo angle -14.1 degrees
Near infrared to nadir stereo angle -2.05 degrees Dynamic Range of CCD - 12-bits for all arrays
All ADS40 camera systems used for this project were equipped with the narrow angle infrared configuration that facilitates production of a natural color and false color infrared composite.
For this dataset, the natural color and color infrared orthoimages were produced at 1.0-meter pixel resolution. The accuracy has been designed to meet NMAS for 1:12,000 maps. Each digital orthorectified quarter quad provides imagery for a nominal 3.75 by 3.75 minute area corresponding to the USGS quarter quad boundaries. The projected coordinate system is UTM with a NAD83 datum. The naming convention is based on the state of Florida DOQQ naming convention.
Deliverables include -
24-Bit (8-bit) Natural Color in GeoTIFF format
24-Bit (8-bit) False Color Infrared in GeoTIFF format
48-Bit (16-bit) Natural Color in GeoTIFF format
48-Bit (16-bit) False Color Infrared in GeoTIFF format |