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| USGS › Geography › Earth Resources Observation and Science (EROS) Center |
Color-infrared NHAP photo |
Black and white NHAP photo |
The National High Altitude Photography (NHAP) program was in operation from 1980 to 1989. It was coordinated by the USGS to acquire aerial photography of the 48 conterminous states on a 5–7 year repeat cycle.
NHAP photography was acquired from an altitude of 40,000 feet. Two different camera systems were used to acquire simultaneous coverage at two different scales. A 6-inch focal length lens acquired black-and-white (B/W) film at an approximate scale of 1:80,000. B/W photos cover a ground area of 11 x 11 miles. An 8.25-inch lens acquired color-infrared (CIR) film at an approximate scale of 1:58,000. CIR photos cover a ground area of 8 x 8 miles.
After October 1, 2009, the USGS film archive collections will be systematically scanned to a standard format High Resolution 25 micron digital image (excluding Declassified Satellite Imagery which will be scanned to 7 micron) and also offered to the public at no charge.
Obviously, the task to create, store and distribute millions of High Resolution Scanned Photographic imagery is extremely challenging, costly and time consuming. With just consideration to the portion of the film collection that will receive highest scanning priority because physical vinegar syndrome deterioration risk, we have an expected 3 to 4 years of work. A scanning plan will be posted on the USGS EROS website with sufficient detail to allow users to review the overall schedule. It will show which collection are currently being worked on, and what progress has been made.
National Aerial Photography Program (NAPP) and National High Altitude Photography (NHAP) will have a lower priority in the scanning schedule and therefore not available for on request scanning for the EROS archive. However, the medium resolution data for these and other film collections will continue to be offered for download at no charge. If High Resolution Scanned images are required for the NAPP and NHAP data sets, we encourage customers to contact the USDA’s Aerial Photography Field Office (APFO) for information on their products, prices, and services (http://www.apfo.usda.gov).
The file sizes are about 15 megabytes for black-and-white images and 40 megabytes for color images. The files are stored in TIFF format. The medium-resolution files are created at about 400 dpi.
All of the medium resolution NHAP and NAPP images have been digitized. Products can be downloaded through EarthExplorer or GloVis. All NHAP medium resolution digitized images are downloadable at no cost.
NHAP photography may also be ordered through the USDA Aerial Photography Field Office (APFO) Businesses that can provide printed images from USGS digital data.
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