## 2 Related Work  
The potential of using PSS images for 3D stereo photogrammetry and 4D change detection was already shown in a few studies, e.g., Refs. [16; 17; 19; 20], with similar workflows and results. The first study, to our knowledge, focusing on DEM generation from PlanetScope data for geomorphological analyses was published in [17]. The proposed method implies a stabilization of the image block applying bundle-block adjustment, here called bias correction. This optimizes the RFMs of the individual images and is followed by pairwise stereo reconstruction applying semi-global matching (SGM) in object space. The resulting point clouds are rasterized into a single DEM with a GSD of 5 m/px using the median altitude in overlapping areas. The DEM is finally co-registered to an already existing DEM to correct systematic shifts commonly resulting from bundle-block adjustment without using ground control points (GCPs) that impact the georeferencing. Details on the implementation, tools, or used libraries were not provided. The method was applied to generate DEMs in high mountain and partial glaciated areas, e.g., Volcano Teide (steep terrain and sparse vegetation; reference DEM from LiDAR) and Naga Parabat Massif (glaciated high mountains and no vegetation; ALOS World DEM (AW3D30) as reference DEM). The authors of Ref. [16] selected suitable image pairs in a first step by examining all the available images of a region of interest (ROI) captured over a certain time period, selecting image pairs with maximum overlap and the best convergence angles. They performed bias correction followed by point cloud generation using Agisoft Metashape's Dense Matching function. The generated point cloud is resampled to a DEM with a GSD of 9 m. The proposed method for bias correction was implemented in the software COSI-Corr, which was originally published as a plug-in for the commercial remote sensing software ENVI from NV5 Geospatial Solutions [21]. Since 2022, COSI-Corr has also been available as a standalone version (e.g., [22]). The approach was used to detect changes in glacier topography before and after a surge event. In a more recent study, Ref. [23] provided more details on how to select suitable image pairs for this operation: The minimum number of overlapping images should be greater than five, the base-to-height ratio should be better than 1:7 with an overlap of at least 60%, and the images should be captured from opposite satellite azimuths, i.e., ascending and descending orbits as well as in short time spans to reduce, for example, weather and seasonal influences on the image representations. In the work of [20], almost all the available PSS images captured in a specific time span were used to generate a DEM of an area with various topographic highlights, e.g., cities, forested hills, and steep mountains. They also performed bias correction as a first step via bundle-block adjustment followed by pairwise stereo reconstruction applying SGM. The individual point clouds were rasterized to DEMs and analyzed for height errors in correlation with the original convergence angle of the stereo pair. Those DEMs generated from image pairs with convergence angles larger than 6\({}^{\circ}\) showed fewer errors and were merged to a single DEM using the median height. Details on the algorithms, implementation, or used tools were not provided. The authors of Ref. [19] evaluated the potential of PlanetScope images for 3D applications with a specific focus on 4D change detection in urban, rural, forested, and glacial areas. They applied an in-house-developed multi-view stereo (MVS) pipeline based on [24] and compared the results with reference 3D data from LiDAR. Similar to [20], they found that accurate DEMs can be generated using image pairs with convergence angles larger than 8\({}^{\circ}\). The accuracy investigations of [17] show normalized median of absolute deviations (NMADs) of the DEMs derived from PlanetScope of 4.1 m compared to a LiDAR DEM and 3.9 m compared to the AW3D30 over stable terrain. The authors of Ref.