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Contrary to aerial images obtained by digital cameras, scanned aerial images are characterized by a lower radiometric resolution and reduced contrast. These parameters have a direct relationship with the quality of the image matching using correlation including the number and accuracy of measurement of tie points in the aerial triangulation. Digital images processing, including filtration in the domain of an object, allows for increasing the contrast, removing noises, and intensifying and detecting edges of objects mapped in the images. This article examines the influence of the key processes of digital image processing on the increase of their measuring and information values. Used in the studies was a block of historical aerial images, covering an area of the western part of Warsaw district, acquired in the 1950s and made available by the Main Centre of Geodetic and Cartographic Documentation (CODGIK). The scope of the study covered the analysis of the impact of selected linear filters, together with high-pass and low-pass filters and also non-linear filters, including statistical and adaptive filters, with different mask sizes, on the accuracy of the field coordinate designation of a tie point in the aerial triangulation. Context operations and also the analysis of contrast correction were carried out in ERDAS 2013. Automatic measurement of tie points together with conducting a relative and absolute adjustment for the block of images orientation were carried out in Inpho 6.0. The results of automatic measurement of tie points for the block of aerial images covered by the radiometric correction were compiled with analogical results obtained for unprocessed images. The measure of the effectiveness of the applied filtration and operations on the images was the mean average error of field coordinate designation of the tie point, the average error of the background coordinate measurement on the image and also the number and distribution of automatically measured ties.
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