We've been using photogrammetry to record parts of our medieval farm site at Bourton on the Hill. This computer-generated animation of the small room featured in our last blog post was produced using photogrammeric techniques.Photogrammetry is an established archaeological recording technique and uses photographs to create reconstructions of buildings, structures and sites. In traditional photogrammetry fixed 'targets' are used as reference points to 'stitch' the photographs together and 'rectify' them to the correct scale and viewpoint. Increases in computing power have led to computer-based photogrammetric programs that can combine many digital photographs to create 3-D models of the subject without the need for targets. The models can be rectified (scaled and located spatially) so that we can then produce scale 2-D drawings from the 3-D model, these drawings are then used in the post-excavation work and as illustrations in the final published report.