to 
(18 a) 
(18 b) 
b 
(18 c) 
After the relative orientation the nadir directions are parallell to 
each other and the ^-rotations have the following- effect on the heights 
of the model 
— 2x 2 + 2bx — b 2 
2R 
dh 
(19) 
The total influence 
The total influence on the elevatoins are received if eq (15) and (19) 
are added. This addition shows that heights measured in a model will 
be equal to geodetically levelled. 
If the curvature of the earth is corrected by a change of the radii of 
the aerial photographs 
1. The influence of the curvature is eliminated in aerial triangula 
tion as well as in the single model. 
2. The model is theoretically free from y-parallaxes without the 
relative orientation beeing accomplished according to the definition. 
References. 
1. OEEPE. Commission A. Report. Amsterdam 1961. 
2. Finsterivcilder, R.: Photogrammetrie. Berlin 1939. 
3. Buchhols, A.: Photogrammetrie. Berlin 1960. 
4. v Gruber, O.: Beitrag zu Theorie und Praxis von Aeropolygonierung und 
Aeronivellement. BuL 1935. 
5. Schzvidefsky, K.: Grundriss der Photogrammetrie. Stuttgart 1954. 
6. Schzvidefsky, K.: Grundriss der Photogrammetrie. Stuttgart 1963. 
7. Öhlin, K. A.: The Influence of the Curvature of the Earth upon Aerial 
Pictures. SLT. Stockholm 1964. 
8. Hattert B.: Über die Herstellung photogrammetrischer Pläne. Diss. Stock 
holm 1944. 
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