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The image data are more often primary power source data supplied many information systems like GIS. However, remember that they are initially recorded in the central projection or dynamic projection, which does not guarantee the required cartometry of objects mapped on the image. To obtain the orthogonal projection of the terrain we need to do secondary, differential processing of the original images to orthophotos. Current technologies implementing this process in a digital form allow the location of each processed pixel of created orthophotos within a given external terrain coordinate system. In this way, all pixels of digital orthophotos have a defined spatial location or georeferencing. In the paper the current state of technology in creating of georeferenced image data (orthophoto and trueortho) is given. They are treated the geometric and radiometric characteristics of these products and their functionality as a reference layer in GIS for different types of sites and applications. The current state of the country orthophotomap coverage and a plan to update it until 2013 is given. Trueortho technology is presented in detail, which should be preferred for urban areas as eliminating obscured areas present on the traditional orthophotoma. They are presented the practical results obtained in the course of experimental work in the framework of the KBN research project "Study on the quality of True-Ortho in terms of used the source data". In summary, the technological recommendations and geometrical requirements are given for source data required to generate the trueortho, as cartographic reference layer in GIS, or 2D source data for capture the vector data for topographic and thematic data bases needs.
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