In this study, we examined the use of photogrammetric surveying with an unmanned aerial vehicle (UAV) for performing the engineering part of cadastral procedures, by analysing the accuracy of the determination of points' positions that define the course of parcel boundaries and of other detailed points. In two case studies, we performed point measurements using the GNSS-RTK method and the tacheometric survey method. Simultaneously, we carried out a photogrammetric survey using a UAV. Indirect georeferencing of photographs was used. Ground control points were measured using the GNSS-RTK method and the tacheometric method. We created two photogrammetric blocks during the processing of UAV images. The first consisted of photographs taken from altitudes of 40 m and 50 m above ground, along with additional images manually captured from a height of 10 m to improve the visibility of certain points. The second block included only images taken from a height of 40 m above ground. The positional accuracy of points determination was assessed based on coordinate differences between measurements obtained with the GNSS-RTK method and the tacheometric method, and the coordinates of identical points determined by photogrammetric restitution. In the conclusion, we provide some guidelines for conducting cadastral procedures using UAV photogrammetry, including guidelines for submitting measurement data in the geodetic survey report.
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