Reprinted from 
PHOTOGRAMMETRIC ENGINEERING 
March 
1955 
DETERMINATION OF THE ACCURACY OF TERRES- 
TRIAL STEREOPHOTOGRAMMETRIC 
PROCEDURES*T 
Dr. Bertil Hallert, Institute of Geodesy, Photogrammetry and. Cartography, 
Ohio State University, Columbus, Ohio. 
INTRODUCTION 
HOTOGRAMMETRIC measurements are generally founded upon com- 
plete information about the inner and outer orientation of the camera in the 
moments of exposure. In terrestrial photogrammetry, all elements of orientation 
normally are assumed to be known from the photography as results of direct or 
indirect measurements, but small errors of course are always present. In aerial 
photogrammetry, on the other hand, the elements of the outer orientation are 
only approximately determined in connection with the photography. Conse 
quently, terrestrial photogrammetry normally means a simpler procedure than 
* Presented at Semi-Annual Meeting of the Society, in Philadelphia, Pa., Sept. 17, 1954. 
t This paper covers a part of a report on a research project concerning the application of 
terrestrial photogrammetry to different measuring problems within cities. The investigations have 
been sponsored by the city of Stockholm, Sweden and have been performed at the Division of 
Photogrammetry of the Royal Institute of Technology, Stockholm, Sweden in cooperation with 
Mr. A. Jórbeck, City Engineer of Stockholm. 
  
  
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