Archaeology and Aerial Photography for Everyone
Can photographs taken such a far distance from the earth actually help us understand cultures that were here thousands and even ten's of thousands of years before? Surprisingly the answer is yes, aerial photos are not only helpful, but essential to the field of archaeology. The idea is actually very simple; many details are just too large to see from the ground, becoming more obvious from a greater distance. In many cases, valuable sites have remained hidden even though people lived within miles, even feet of them. The problem is that from the ground the site appears as scattered rocks, a shallow depression, or even a slightly different color in vegetation. The natural features we see around us could actually be the remnants of an ancient culture. It is not until the site is viewed from above that the land gives up its secrets and that shallow ditch turns into a long forgotten road or the perimeter of a large village. Aerial photography has insured the discovery, mapping and preservation of many important finds.
Archaeological sites remain hidden to us for many reasons, and without proper aerial mapping many have been lost to us forever. In the early days of aerial photography archaeologists would climb to the highest vantage point in order to view known sites, taking pictures to document the find. Today's technology allows archaeologists, and anyone else interested, to photograph their finds from every height and angle. Archaeologists venture out in early morning or late evening, the best light for catching what are known as shadow marked sites. They cover a vast area looking for anything that might still be above ground. If Archaeologists are more interested in finding walls buried far below the ground; then late fall and spring would be the optimal time for photos, due to the walls effect on soil color and vegetation. When remains affect surrounding soil and vegetation they are called soil and crop marked sites. This type of site gives a positive or negative color change visible to the naked eye. This effect may be caused by a change in the soil content, absorption or possibly both and is almost impossible to detect at ground level.
The leaps and bounds that photography has made in the last fifty years have also contributed to the way we study ancient cultures. Archaeologists use high contrast black and white photos to view details in Grey-scale, this works especially well with shadow marked sites. Recently High contrast color photographs have been used to convey the terrain and show much more detail. Color photos are also essential for photographing crop marked sites since color is the only indicator. Even more advanced are Infra-red Photography and satellites. Infra-red measures electro-magnetic energy, giving an alternate view of the area. Satellites, on the other hand, constantly photograph and monitor sites everywhere, including those that are unexplored. By combining all the photographs taken at different times of the day and the year, archaeologists began to get a feel for the way entire areas were settled, putting the pieces together like an ancient puzzle. Although sometimes the pieces are missing, adding field excavation and hard work, helps to form an idea of what it all means.
The great thing about aerial photography is everyone can do it; all that's needed is a vantage point and a camera. Flying over the U.S. on a clear day, many sites can be viewed just by looking out the window. If you ever wondered how those circles were made in the middle of huge fields in Iowa or what the light grid pattern was on the desert below, it is possible what your seeing is a settlement, burial site, or ancient road. For an interesting way to pass the time during an overland flight, count the possible archaeological sites. Comparing them to a list of known sites in the area may even reveal a new discovery. Known sites can be found on the website of the area's college or university or by contacting the Archeology Department.
Emporia State University, Kansas USA www.emporia.edu
University of Vienna Archives, Austria www.univie.ac.at