2 
J 
The distance g between the axis of the swinging girder and the image 
centre is 185 mm in the A 5 and 230 mm in the A 7, as measured in the 
diapositive plane. Tables have been computed for the Wild A 7 of the 
; cadi S dy X 
partial derivatives 777 and — 
s S 
In the computation procedure, the observation equations of [1] are 
augmented with the right members of eq. (1 x) and (1 y). The normal 
equations are formed and solved according to the method of least squa- 
res. It 1s evident that the latitude distortion and the x-inclination will be 
correlated with the errors of translation and rotation. 
As an example, the results of an instrument test of the Wild A 7 No 
310 shall be quoted. Coordinates were measured in 25 points of one pro- 
jector. The measurements were first computed without consideration 
to the x-inclination and latitude distortion. The standard error of an 
observation was then 7.15 microns in the diapositive plane. When the 
two columns of partial derivatives of the measured coordinates with res. 
pect to dt and dl were added, the standard error was reduced to 4.43 
microns. A considerable amount of longitudinal displacement (dl = 
44.5 microns in the diapositive plane) was discovered, indicating that 
the instrument needed adjustment. 
Reference 
[1] Hallert, B.: Tests of Fundamental Photogrammetric Operations. The Photo- 
grammetric Record. April 1955. 
  
  
  
  
  
  
  
  
  
     
  
   
    
  
   
   
  
  
  
  
  
  
   
   
  
  
   
  
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