Imagery intelligence

Imagery intelligence (IMINT) is a means of obtaining information about distant topics by creating an image of it, most often using visible light photography. Photointerpreters are people skilled in understanding the significance of images, such as high-altitude photographs of camouflaged military installations. They may use quantitative techniques of photogrammetry, as well as a highly trained ability to recognize patterns. It is a subset of geospatial intelligence, which matches the images to precise geographic positions.

Imaging sensors, as a first approximation, break into "mapping" (or "wide-view") and "close-look" types. Accurate maps are indeed a product of imagery intelligence, as well as geodesy. Wide-view imaging, coupled with spectroscopic MASINT, can give significant economic intelligence relating to the state of agriculture, disasters, and natural resources. Close-look techniques can identify specific patterns and individual objects; a Soviet S-75 Dvina installation, for example, had a characteristic six-pointed star pattern even if the missiles and radars could not be seen in detail. Of course, given a clue that a given missile radar system might be in a certain place, electronic intelligence can be tasked to confirm by detecting the radars of that system.

Given a precisely located image, the full range of intelligence collection technologies can cooperate to understand its significance. Spectroscopic MASINT, for example, does not create new images, but analyzes the infrared and visible spectra of the pixels of the image. Multispectral analysis of those pixels can reveal, for example, if a field, grass-green to the human eye, is actually vegetation or camouflage paint. Signals intelligence can determine if communications or radar signals are coming from a seemingly innocent building.

The image-forming devices are most often on reconnaissance aircraft or satellites, but can come from handheld cameras on the ground, photographs taken through a submarine's periscope, or many other potential platforms. Imagery intelligence definitely includes photographs taken in the infrared or ultraviolet spectra.

Electro-optical imaging

Electro-optical imaging is a superset of photography in the visual and infrared spectra, using precise cueing to direct the cameras, correlating them with precise time and geographic references.

Radar Imaging

See imaging radar.

Sensitivity of information

For many years, U.S. imagery intelligence taken by other than tactical systems were under the TALENT-KEYHOLE (TK) compartmented control system. TALENT applied to airborne and KEYHOLE to satellite systems, but the product was so commingled that separation made little sense. While the Soviets knew about U-2 aircraft photography almost from the first flight over their homeland, they did not, at first, know about satellite imagery and special sensitivity was warranted.

Later, "the fact of" satellite imagery was kept highly classified due to Soviet sensitivities. They considered it politically unacceptable to have "spy satellites over the Motherland", and the great Red Army unable to do anything about them. Soviet delegations threatened, apparently seriously, to walk out of arms control conferences if the information was made public.

Operational military commanders grew more and more upset that combat aircrews, who rarely had TOP SECRET/TK clearances, could not see pictures of the targets they were going to attack. Most imagery useful at the tactical level is now at the SECRET "collateral" (i.e., not in a compartment) level. For photographs of special sensitivity, especially digital ones, the resolution can be artifically reduced so the sensor capabilities are not used; some examples of such have been released to the press.