ISP Investigation into the Accuracy of 
Photogrammetric Triangulation 
by 
  
X. Kubik” and J. Kure 
m Background 
The problem of establishing the accuracy of photogrammetric triangulation is 
as such concerned with the definition of the nature, distribution and sources 
of the errors occurring; the determination of how these errors are influenced 
by parameters such as type of camera, type of instrument, bridging distance, 
etc. and how these basic errors propagate through the triangulation or 
computational process. 
Hitherto, both empirical and theoretical investigations have been carried out 
in order to establish the required accuracy models of the triangulation process. 
| The expensive and time-consuming empirical tests have only been carried out 
| extensively by international organisations such as the ISP and the OEEPE. 
© e (sce [1] & [2] ) - the most recent being the Oberschwaben experiments, [3]. 
| The main disadvantage of these empirical tests is that they give the combined 
| effect of all errors involved. These are then generally difficult to separate 
unless a large number of experiments are carried out, varying a single 
influencing factor at a time. 
Furthermore, the results of these experiments cannot be extrapolated to other 
conditions not contained in the experiment i.e. other terrain types, other 
atmospheric conditions, etc. 
The main theoretical investigations carried out with simplified error models 
can be classified into the following main groups : 
— Accuracy of planimetric strip and block triangulation based on the 
independent model approach; Ackermann [4] and Ebner GE 
— Accuracy of height strip and block triangulation based on the theory of 
transfer errors ; Jerie [6]. 
— Accuracy of planimetric and height strip and block triangulation based 
© & on the bundle approach; Kunji [7] , Talts [8] and Kilpela [9]. 
x) 
Now with the Data Processing Dept., Rijswaterstaat, Delft