Increasingly, remote-controlled aircraft are used in the surveying field, especially for photogrammetric
capture of images for obtaining 3D data in the form of a point cloud and for the production of 3D models
and orthophotos. In the thesis, we experimentally tested how the ground sampling distance of images
affects the positional accuracy of products, which in our case are point clouds, digital terrain models and
orthophotos. We took images in several time series where we performed flights at 37, 74, 93, 112 and
130 meters above the ground level. Flight heights were determined based on the desired ground sampling
distance of the images. During the shooting we also recorded the weather conditions in each serie so
that we could take this into account when analyzing the results. In the theoretical part of the thesis, we
briefly introduced a new field of SfM-photogrammetry, we described the relationship between flight
altitude and the ground sampling distance of images, and the appropriate distribution of ground control
points. We calculated an estimation of the accuracy of the geodetic network, on the basis of which we
determined the positions of the ground control points that are needed to orientate the captured images
into the reference coordinate system. In the practical part of the diploma thesis we described data
acquisition and processing. In the analysis of the results, we compared the positional accuracy of
products made from images of different spatial resolutions. In our case, we set the economically optimal
resolution of the images. This is the highest possible resolution of images, which still provides the clarity
of detail and the desired positional accuracy of point clouds, digital terrain models and ortophotos.
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