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U.S. DEPARTMENT OF THE INTERIORBUREAU OF LAND MANAGEMENT
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| BLM Aerial Photography | ||||
Aerial Photography Archive
B & W Negative FilmsPrior to 1970, all of BLM's aerial photography projects were flown with B&W negative film. This general purpose coverage will yield B&W paper print or film products suitable for a wide variety of uses relating to surface mapping and/or interpretation. With the absence of color, certain limitations for its utilization can be expected. However, the historical data contained within the B&W film portion of the archive is proving to be invaluable for change detection studies conducted in a variety of disciplines. Medford, Oregon Black and White Examples
Full 9X9 photo | Enlargement | Enlargement Natural Color Negative FilmsThe largest portion of BLM's aerial photography coverage exists as natural color negative film. This original film, once exposed and developed, is in "complimentary" negative form. When reproduced through conventional means as either a paper or film product, the resultant reversed or "positive" image appears just as the human eye would perceive it, a natural color scene. Photo interpretation applications for this daylight exposure film are almost endless. Medford, Oregon Natural Color Examples Full 9x9 Photo | Enlargement | Enlargement Moab, Utah Natural Color Examples
Full 9X9 photo | Enlargement | Enlargement Medford, Oregon Natural Color Examples
Full 9X9 photo | Enlargement | Enlargement False Color Infrared FilmsThese films comprise a much smaller portion of BLM's film archive. Due to the unique characteristics of this film, false color infrared is preferred for vegetative and hydrologic studies. False color infrared film is sensitive to ultraviolet, visible and infrared radiation to approximately 900 nm. When the film is exposed with a yellow filter, the emulsion layers become sensitive to only green, red and infrared wavelengths. Blue radiation is absorbed by the filter; hence, the greater haze penetration ability of infrared film. The most obvious characteristic of false color infrared films is the distinctive pink to magenta coloring of most live and healthy vegetation (exclusive of many conifer species). Almost all surface features distinguishable with B&W or natural color film can also be distinguished with false color infrared reproductions (assuming said features are NOT reliant on "natural" color differentiation as would be the case with some geologic profiling.) This photography does not capture ambient temperature variation as is the case with other types of thermal imaging. Moab, Utah Infrared Examples
Full 9x9 Photo | Enlargement | Enlargement If you have an interest in ordering reproductions from BLM's film archive, please contact our staff with detailed information on your specific target area. We'll be happy to research and determine availability of coverage for you given such aides as state, county, nearby cities, and/or geographic coordinates (latitude/longitude or township/range/section numbers). In some cases, we may even need a map to pinpoint small parcels of land or surface features. Once we've designated the projects in our archive that are pertinent, we can outline the options for product availability, respond to any questions you may have, and finalize any associated costs for products ordered. You can also research the flight lines and aerial project boundaries yourself on an Interactive Map providing detailed land descriptions, topo maps, aerial imagery and more.
Interactive Mapping All orders will be assessed a $10 shipping and handling fee and must be prepaid. The BLM accepts checks and credit cards. For more information, including pricing, or to place an order, please contact OrderAerialPhotos@blm.gov. |
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