Photogrammetry is the use of photography to derive the geometric properties of objects. Individual graves are photographed between 40 and 100 times from different angles and photographs are then dropped into a photogrammetry program. The software creates a 3D model of the object photographed, and this object is then tied into the excavation grid using survey points shot in with the on-site electronic theodolite.
Download a 3D rendering of a burial here: HB_09 (pdf). A blank page will come up – choose to “Save As.” You must have a PDF reader such as Adobe Acrobat to manipulate the object. The model was made by Giles Morrow at the University of Toronto, and was sent to us while were were still in the field.
This video offers another look at how we use photogrammetry: