CS4SEHAG - Historical terrestrial images

Within the CS4SEHAG project we developed a citizen science app to engage citizens into the documentation of high-alpine regions. To drive (initial) engagement, we estimated the position and orientation of over 100 historical terrestrial images from the AKON postcard portal of the Austrian National Library. This dataset contains the estimated camera parameters (position, orientation, focal length) as well as reference points, which were used to calculate the camera positions. For the estimation of the camera parameters we used moniQue, which is a QGIS plugin for the estimation of camera parameters and monoplotting. The positions in object space are provided in meters, whereas in image space (for the reference points) the coordinates are in pixels. For the Euler angles we used radians. All attributes with the suffix "_std" represent the standard deviations of the esimated parameter. For the reference points the residuals in image space are represented by the two attributes with the suffices "_dx" and "_dy". The coordinate system for each camera is given by its EPSG code and is either 3035 (ETRS89-extended / LAEA Europe) or 25832 (ETRS89 / UTM zone 32N). 

The images are mainly located in Tirol and South Tyrol and were acquired between 1890 and 1950. To get more information for each image we provide the link to the original metadata within the cameras.json. Furthermore, we provide example code to enable users to transform the provided Euler angels (describing the orientation of the camera) into a rotation matrix that can be further used.