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The results of research on the use of new technologies in national aerotriangulations have been presented, in particular the technology of integrated sensor orientation. The aim of this study was to determine the state of design and implementation of aerotriangulations in respect to GCP design and obtained precision and reliability of measurements. The study was based on the results of 19 actual aerotriangulations made in the country in the years 2008–2010. The blocks selected for study were made with a large-format digital camera and more than 90% of images had measurements of GNSS / IMU. They were calculated again with Bingo software to remove the occasional factual errors and to standardize the statistical evaluations. The designs of GCPs were rated by considering their number and distribution in the block. For the examined sample of blocks the range of variability of the precision of measurements was determined together with its mean values. The obtained mean values of the precision were compared with the capabilities of current measurement techniques. Also the average reliability of individual groups of measurements in aerotriangulation was determined and the average accuracy of determination of the ground coordinates of tie points. The precisions of measurement in the sample blocks do not differ from those obtained in other countries. The conclusions of studies concern changes in requirements for the number of ground control points in the block because in rated blocks, this number is usually far too high. The conclusions also postulate to improve two components of the technology, namely: one – a closer link between the calibration of measuring sensors with the periods of stability of their systematic errors and two – the increase of the precision of target of GPC and the precision of measurement of the targeted GCP in the images. The results and conclusions of the research will be able to serve in formulating conditions for performing aerial triangulation and will be used in simulation studies of aerial triangulation to determine the desired number and density of GCP for large blocks calculated with the use of the technology of integrated sensor orientation.
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