(4) 
  
coss 
In figure 4 the standard error of the average of the 
distortion has been plotted for y - O.ol mm. [4] As in- 
dicated in the figure, the accuracy of the distortion de- 
termination is almost equivalent for different radii and 
as an average of the standard error a value of 0,6 u may 
be used. 
The irregularities in the pictures, discovered through 
the y-parallax measurements, may of course constitute a 
base for a qualitative comparison of the geometrical pro- 
perties of the different kinds of negativ material. 
Consequently we computed the y-parallax, remaining in 
each point, after the adjustment of the relative orienta- 
tion and after the correction of the distortion according 
to the average distortion curve. The mean square value of 
these residual parallaxes was determined for each group 
of four symmetrically located points (see table 1). 
Table 1 
The mean square value of the y-parallaxes after adjustment 
of the relative orientation and correction of the distortion(p, ). 
The mean square value of the deviations from the average dis- T 
tortion curve (dr). 
  
  
  
  
Panchromatic Infra-red Colour 
0.01 i 0,01 mm 0.01 mm 
r 
By. Bye ar £P ar 
1,23 1.31 0.32 0,32 0.94 0.94 
0.76 0.78 0.81 0.82 0.89 0.90 
1.13 1.156 0.93 0,95 0.44 0.49 
1.55 1.40 0,82 0.86 1.04 1.10 
0.57 0,62 0,59 0.63 0,95 1.02 
0.56 0.65 0.61 0.68 0.64 0.73 
1.15 1.39 0.40 0.46 0.535 0.40 
0.78 0.96 0.59 0.49 0.17 0.22 
0.52 0,50 0.29 0.40 0.45 0.58 
0.86 0.97 0,58 0.62 0.65 0.70 
mean value 
    
   
  
  
  
    
   
  
    
   
  
   
   
   
  
  
  
  
  
  
  
  
  
  
  
   
    
    
   
   
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