PHOTOGRAMMETRIC ENGINEERING 
90° 
MECHANICAL |/7 Sols. 
Axls -— 3 >, 
e NN UTR / 
XE 
een 
RS 
Qo 
  
  
Fic. 9. Double reading circle. 
There are several methods of determining the errors, and axis, of circle 
eccentricity. It is felt that an analytic solution making no assumption regarding 
sine curve behavior is the more desirable. The analytic solution]is illustrated 
in Figure 10. 
Y 
  
x SES CEWTER 
  
  
  
| MECHAMICAL 
\ AN CENTER 
| | y. 
\ 
\ NE 
N — an li : 
N | ine Ç 
Fic. 10. Circle eccentricity. 
4 
A