An aerial photograph shows much more than archaeological features and by reading that information, especially the non-archaeological elements, we are often able to place an archaeological site in its contemporary context, such as
a location. Photo reading of this kind is one of the early stages of examining aerial photographs and is a useful time
to discuss findings with colleagues. Discussion, reflection and constant questioning are necessary to improve the
skills and knowledge of a photo interpreter.
Photo interpreters identify, depict and describe features of archaeological interest as well as any others that
may be relevant to our understanding of them. Context may be shown by mapping natural and recent features
and work done prior to excavation may attempt to show and classify anything that will be seen once topsoil has
In order to trace archaeological features from oblique images and integrate them into a map we must distort
and move the original oblique photograph. This process known as georectification is usually carried out before
final examination has been done by the interpreter. Within each oblique photograph at least four objects (ground
control points) are identified which can be seen on a detailed map. Using image processing software, the oblique
image is the stretched or transformed so the ground control point on the photograph align to those on the map.
This process is only really applicable for areas where there is little or no relief in the landscape as this can cause
distortion in your oblique image also. For these situation archaeologists will use photogrammetry.