> 
p. 
$6 
8 ! +.45 
  
Fig. 3. Practical example of the determination of the radial distortion from measu- 
red y-parallaxes. The measured y-parallaxes are indicated for each point and are 
given in units of 0.1 mm. b = d. 
The pictures were taken by the U. S. Coast and Geodetic Survey, 
USA. 
The pictures (diapositives) were oriented in the Autograph A7 No. 
310 at the R. Institute of Technology, Stockholm. After a numerical 
orientation, the residual y-parallaxes were measured stereoscopically. 
The results of the measurements are demonstrated in fig. 3.