2007 MrSID Image of St. John Utilized to derive Benthic Habitat Maps (18064_c6_ne.sid)

This MrSID (.sid) file is an orthophoto mosaic from a collection of GeoTIFF format natural color and false color infrared orthophotos covering the islands of Puerto Rico, Culebra, Vieques, St. Thomas, St. John, and St. Croix (USVI). An orthophoto is remotely sensed image data in which displacement of features in the image caused by terrain relief and sensor orientation have been mathematically removed. Orthophotography combines the image characteristics of a photograph with the geometric qualities of a map. The source imagery was obtained from November 2006 through March 2007 and used to produce orthophotos with a one foot ground sample distance (GSD). Imagery was acquired at 0.9 foot GSD resolution. Flight height maintained during mission was 8,650 feet AGL. The imagery was captured at 12-bit radiometric resolution and converted to 8-bit radiometric resolution during post processing. The imagery was captured with 30% sidelap between all adjacent flight lines. The PRVI project area was divided into 20 flight blocks due to neccessary base station and flight line length requirements. The imagery was obtained and processed by all digital means beginning with data acquisition using an ADS40 digital sensor. The orthophotos are also available in GeoTIFF form from the distributor.