Multitemporal Archaeological Imagery to Model the Progress of Excavation

The progress of excavation work has been regularly recorded by taking images during the excavation seasons of Finnish Jabal Haroun Project. This multitemporal archaeological imagery is collected during 1998-2003. Images have been taken daily from the archaeological excavation site, namely the monastic complex of St. Aaron located near Petra, in Jordan. The images have been taken with non-metric digital camera and with non-metric video camera with varying imaging strategies. Large amount of images are convergent panoramic images taken by rotating the camera on the tripod around the projection center. Also separate images and some stereo pairs are available. The aim in the project has been to develop simple documentation methods for archaeologists and therefore minimum preparations are needed during the fieldwork to minimize the disturbance for excavation work. Use of signalised control points is minimized. During excavation season basic geometry of the site has been measured with a tacheometer. In some cases natural control points have been measured with the tacheometer and marked on the printouts. The 3D tacheometer data can be used for solving the orientation parameters. The possibilities to use the collected imagery are presented. The progress of excavation is visualized in one example area – the chapel. The images have been organized by date and their rough orientation relating to the chapel is known. The images are taken from different angles relating to the excavation trenches (the chapel has been excavated in several steps). Therefore a simplified 3D model is used as a visual aid to show the orientation relating to the model. The user can study the available imagery and select the appropriate images for further processing. The original image orientation can be re-fined in case the images are utilized for detailed modelling of the site. The preliminary tests confirm that it is possible to complete the 3D modelling of the excavation site using the collected imagery and basic photogrammetric methods.