Cost-effective geocoding with exterior orientation for airborne and terrestrial archaeological photography - possibilities and limitations

Taking a photograph is often considered to be an indispensable procedural step in many archaeological fields (e.g. excavating), whereas some sub-disciplines (e.g. aerial archaeology) often consider photographs to be the prime data source. Whether they were acquired on the ground or from the air, digital cameras save with each photograph the exact date and time of acquisition and additionally enable to store the camera's geographical location in specific metadata fields. This location is typically obtained from GNSS (Global Navigation Satellite System) receivers, either operating in continuous mode to record the path of the camera platform, or the position is observed for each exposure individually. Although such positional information has huge advantages in archiving the imagery, this approach has several limits as it does not record the complete exterior orientation of the camera. More specifically, the essential roll, pitch and yaw camera angles are missing, thus the viewing direction and the camera rot...