In recent years, direct georeferencing of Unmanned Aerial Vehicles (UAVs) has been perfected with built-in Real-Time Kinematic (RTK) and Post-Processed Kinematic (PPK) measurement modules, which enable real-time or subsequently positioning. Both methods have their advantages and disadvantages, but at the same time they complement each other when one of them cannot be used due to different situations (eg terrain characteristics, non / accessibility of the mobile network …). In the research, we tested the Phantom 4 RTK aircraft in the area of the Strunjan cliff along the Slovenian coast of the Adriatic Sea. The test area included several recording missions, the positions of which were determined in real time by connecting to the D-RTK 2 Mobile Station and subsequently based on GNSS observations from our own reference base stations in the vicinity of the survey. The positions of the projection centers of the images obtained by the RTK and PPK methods were compared with each other. Based on the coordinate differences, we determined whether different locations of base stations affect the quality of the PPK solution and whether the latter differs significantly from the RTK solution. The article also presents the issue of PPK processing. The results show that the choice of base station location can affect the quality of UAV positioning. The coordinate differences between the RTK and PPK solutions average 0.3–8 cm in the ^ and ^ directions and 1–6 cm in the ^ direction.