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Communication to 
VIII International Congress for Photogrammetry 
Reprint from 
Svensk Lantmateritidskrift 
Congress Number 1956 
Commission II 
SUGGESTION FOR A STANDARDIZED TEST OF THE 
PROJECTION SYSTEM IN PHOTOGRAMMETRIC 
PLOTTING INSTRUMENTS 
+ B. Hallert—E. Rehnlund 
Stockholm 70 
Introduction 
The reconstruction of the pencils of rays from photography is a fun- 
damental operation in photogrammetry. Therefore the quality of a cer- 
tain instrument is very closely connected with the geometrical quality of 
the projection system. It therefore seems very desirable to establish a 
test procedure that allows a well defined determination of the accuracy 
of the reconstruction of a given central projection. The test procedure 
shall also allow a determination of possible systematic errors of the 
projection system, first of all the radial distortion, but also asymmetries 
of various kinds. A complete determination of the inner orientation of 
the projection system is also desirable. Such a test procedure has to be 
performed with the aid of measurements. Consequentiy the measuring 
errors have to be treated in a well defined way. 
Jelow a suggestion is made for such a test procedure. 
The grid method, [1], [2], [3] 
for the test procedure. 
  
  
and [4] is used as the basic method 
1. Determination of the radial distortion 
The radial distortion is probably the most important disturbance in 
the photogrammetric pencils of rays. It 1s also very important to test 
the performance of different devices for correction of a certain radial 
distortion that is assumed to be present in the pencils of rays from the 
photography. 
Therefore we will pay special attention to the determination of the 
radial distortion in the projection system. 
i H 
  
  
R9 
iT ARCHIVE” OF 
Appendix te the INT, AP C! 
PHOTOGRAMMETRY, Vel, Xlk4, 1956 
  
  
  
  
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