GEOMETRIC ASPECTS CONCERNING THE PHOTOGRAMMETRIC WORKFLOW OF THE DIGITAL AERIAL CAMERA ULTRACAMX

In this paper we give a detailed description of the photogrammetric workflow recommended for the large format digital aerial camera UltraCamX. This includes image pre-processing, automated aerotriangulation (AAT) and the derivation of the final product (DTM, orthophotos, etc.) High quality geometric camera calibration is a prerequisite for photogrammetric applications. We will therefore also describe the initial camera calibration performed by Vexcel and the temperature dependent model (TDM), which compensates for systematic sensor drift during OPC post-processing. Geometric properties of the image also depend on the (variable) flight conditions (e.g. radial distortion caused by refraction). Self-calibration should therefore be applied in the final bundle adjustment to achieve the highest possible accuracies. We present self-calibration parameters suitable for the UltraCamX, consisting of traditional parameter sets and parameters specially designed for the UltraCamX. Geometric corrections described by these parameters must be applied to avoid systematic errors in the final product. To document this, we simulate systematic errors in the exterior orientation parameters and the DTM surface caused by systematic image errors