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The following instruments are used for topographic mapping in our photogrammetric 
establishments: 
Stereoplanigraph, Zeiss-Jena 
Stereometrograph, Zeiss-Jena 
Autograph Wild A5, A7 and A8 
Rectifier SEG I 
Stereocomparator Zeiss-Jena 1818. 
II. Large scale mapping for technical and economic purposes 
In Czechoslovakia the need of new large scale maps especially for technical purposes led 
the Government to issue a decree in 1962 entrusting the Central Office of Geodesy and 
Cartography with the task of turning out new maps in accordance with the needs of the natio 
nal economy. For these new maps one of the following scales 1 : 5,000, 1 : 2,000, 1 : 1,000 
exceptionally 1 : 500 was to be used and the mapping was to be carried out over large parts 
of our State territory. Taking in consideration the advantages of the photogrammetric me 
thods and the experiences acquired in topographic mapping by this method (on scales of 
1 : 25,000 and 10,000) it was decided to use photogrammetric methods for this large scale 
mapping. 
The Research Institute of Geodesy, Topography and Cartography is carrying out a wide 
research programme concerning the technology of photogrammetric methods, which residted 
in the publication of the provisional Instructions for large scale mapping on the above menti 
oned scales. These Instructions deal with the main principles of this technology, especially the 
universal photogrammetric method based on the use of universal instruments of the 1st and 
2nd order, equipped with recorders making it possible to apply the numerical method. 
During the last 4 years the Research Institute of Geodesy, Topography and Cartography 
has carried out many experiments aimed determining the most suitable way of aerial photo 
graphy, photogrammetric marking of given and determined points, the ways of photogrammetric 
plotting of the relief and planimetry. Since 1962 all experiments have been carried out on a 
special experimental territory, where on an area of 5 km 2 there are 292 stabilized points. The 
distance between them is about 140 m and the area is mapped on 4 sheets on the scale of 
1 : 2,000. The points are determined with a mean error in position of ± 2 cm and a mean error 
in altitude of + 3 mm. In experimental aerial photography different types of signs are used for 
marking of these points. The signs most frequently used have the form of a four-armed cross 
with the length of the arms corresponding to the scale of the experimental photography. In 
tense research work was carried out recently in order to determine the possibility of applying 
analytical photogrammetric methods for the detailed plotting of photographs particularly for 
supplying the given geodetic points. The theoretical basis of the analytical methods used in 
Czechoslovakia, was elaborated particularly by Ing. Tomsa CSc and Ing. Kratky CSc. The 
computations are effectated by the Minsk-I, ZRA-I, National Elliot 803 and Sirius computers. 
The technology of the universal photogrammetric method on large scales is based on two 
series of aerial photography. Generally the first series are taken in spring and serve the deter 
mination of control points and other points, the investigation of land proprieties and the ela 
boration of the project of the photogrammetric marking of the given and determined points. 
The real aerial photography takes place in the late summer after the harvest. Diapositives are 
made from the aerial photographs and the enlarged photographs are elaborated on the map