Oblique aerial photographs - an "old-new" data source

New imaging platforms, progress in digital cameras, the use of GNSS/IMU technology either in direct sensor orientation or in integrated sensor orientation, new thinking with regard to control information in georeferencing, and co-operation between two disciplines – photogrammetry and computer vision – have brought the possibility of using oblique aerial photographs as a data source into the limelight. This article sheds light on the history of oblique aerial photographs, gives information about related practical experiences, and envisions the possible near future related to this new-found photogrammetric data product. An important new finding of this study is the use of time-series of oblique photographs for enabling image orientation in structure-frommotion software.