ti sina, 
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Now the radial distortion of the different radii can be computed. We get: 
dr’, = + 3:9 microns dr’; = — 13:6 microns 
dr'iz +59 ,, ar'e = — 94 , 
d's= 00 , dr, zm — 14-1. ,, 
a= —37 , dr; = —261 ,, 
The distortion curve can now be drawn (Fig. 2a.). 
A determination of the standard error of the measurements according to the 
adjustment has given the following result: 
6’, = + 3-4 microns Wı= + 9-1 microns 
Maz +47 , 6; = + 55 
[P Em + 2-3 5 
If #’ is assumed to be 5 microns, we get the following values of the standard error 
5», 
of the distortion: 
m', — m, — m', — m', — m', — m, — + 2-5 microns, 
m', — + 1-8 microns, 
m', — -+ 3:5 microns. 
  
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