COMMISSION Ir La | 
. ARCHIVES OF 
| PHOTOGRAMMETRY, Vol. XlE4, 1956 
Appendix to the INT 
  
Communication to 
VIII International Congress for Photogrammetry 
Reprint from 
Svensk Lantmäteritidskrift 
Congress Number 1956 
Commission TI 
NUMERICAL ADJUSTMENT OF X-INCLINATION AND 
LATITUDE DISTORTION IN STEREOSCOPIC 
PLOTTERS 
L. E. Lycken 
In [1], B. Hallert has developed the grid method for the determina- 
tion of systematic deformations of the pencils of rays in stereoscopic 
plotters. This method, which in [1] has been applied to the determina- 
tion of translations, rotations and radial distortion, may of course be 
extended to all kinds of systematic errors. 
In the Wild stereoplotters A 5 and A 7, x-inclination and latitude 
distortion (x-Schiefe and Breitenfehler) are of a systematic character. 
It would hardly be possible to adjust the instruments perfectly, so there 
will always remain a certain amount of errors, caused by those imper- 
fections. In this paper a method for numerical determination of the 
sources of such errors shall be demonstrated. The quantities of errors 
determined may serve as a check of the adjustment situation of the in- 
strument, or they may be used for numerical computation of correc- 
tions to the measured coordinates and parallaxes. 
Latitude distortion and x-inclination appear because the collima- 
tion line of the measuring system fails to coincide with the normal to 
the diapositive plane from the centre of the lens carriage cardan. A 
displacement in the longitudinal direction of the swinging girder will 
result in latitude distortion, a lateral displacement in x-inclination. 
In the following deductions dl denotes a longitudinal and dt a lateral 
displacement of the measuring mark (M), projected through the ob- 
jective into the diapositive, in relation to the orthogonal projection (P) 
of the centre of the upper cardan on the diapositive plane. The deduc- 
tions will be made in the projection plane, i. e. the axis of the swinging 
girder will be considered as placed in front of the projected image area. 
The following relations may easily be derived from the figure by 
means of a simple coordinate transformation: 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
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