3 
INTRODUCTION 
During the period between the IXth and Xth Congress of the International Society for 
Photogrammetry photogrammetric methods were widely used to compile topographic maps on 
a scale of 1 : 10,000 as well as technical maps on scales of 1 : 2,000 and 1 : 1,000. Besides 
mapping the photogrammetric methods were used in forestry, geology, in projects of drainage 
and irrigation, yardage determinations and other technical branches. 
Photogrammetric surveys are carried out by different institutions managed by the Central 
Office of Geodesy and Cartography which is the surveying authority of Czechoslovakia. The 
supplementing of basic maps by special data and thematical surveying, e.g. forestrial, geolo 
gical mapping as well as the compilation of maps for other purposes are carried out by insti 
tutes of the pertaining central authorities as for instance by the Ministry of Agriculture, Fo 
restry and Water Economy, the Central Geological Institute etc. 
Aerial photographic surveying of our State territory is carried out by one single centre 
and serves different photogrammetrical purposes. Specially adjusted airplanes Li 2 of So 
viet production are used for aerial surveying. The most widely used aerial survey cameras are 
the Zeiss- MRB cameras with the Pinatar lens (f = 210 mm), the Wild RC 5a with the 
Aviotar lens (f = 215 mm) and the Aviogon lenses (f = 115 mm and f = 150 mm). 
For surveying we use only vertical photographs. No gyro-stabilization of axis verticality of 
aerial surveying cameras, nor any other devices determining the exterior orientation of photo 
graphs have been employed hitherto. 
I. Topographic mapping 
The aerial photographs for topographic mapping are also taken by the above-mentioned 
cameras. We use photographs on scales of 1 : 13,000 (f = 21 cm) and 1 : 18,000 (f = 11 
cm). For triangulation and for photogrammetric plotting diapositives on flat glass plates are 
used which are made in suitable time after the air-surveying. According to our experiences this 
takes place 15 to 30 days after the original negatives have been produced. For the production 
of diapositives we use electronic printers of Czechoslovak construction as well as printers of 
the Cintel-system. 
The existing net of trigonometric and lower-order points (1 point on 1 km 2 ) for the pho 
togrammetric survey is completed by stereo-triangulation to place at least five control points 
(1 of them is in the center of a pair) on each stereoscopic pair. 
During the period from 1960 to 1963 we used universal plotting instruments, especially 
those of the A7 type equipped with the coordinate recorder EK-5 the densing of an area of 
over 7,000 km 2 was carried out and the net of an area of about 1,100 km 2 was densed by 
applying the analytical aerotriangulation method. 
For topographic mapping on the scale of 1 : 10,000 we mostly use the photogrammetric 
universal method for plotting the relief and planimetry. 
During the period from 1960 to 1963 a territory of about 40,000 km 2 was surveyed by 
photogrammetric methods; 96 % of this area was surveyed by the universal method.