wv 
T AN 
o 
springs M. The distance between lens and focal plane is so established in a very simple way and 
with high accuracy by the ring rotation. 
M 
10 
poete pe qt 
  
  
  
  
oo M cna — E € — 
-40 x 
M 
10 Le eer un 
— 2 ~ w 
2m t € Sá — 
20° TIN 40° = 
— 40 > 
  
  
Fig. 18 - Infinity and close-range distortion of a ''six lenses'' lens 
    
n 
D 
NA 
   
  
    
  
  
      
  
  
  
  
  
Fig. 19 - Veroplast camera : lens movement 
— 49 —