NGC6752       c
 8 iterations.
Chebyshev coeffients a(0)T_0(u)+a(1)T_1(u)+..., where u is log (r/arcsec) mapped to [-1,1]
 a(0)=    18.773 +-  0.072
 a(1)=     5.403 +-  0.128
 a(2)=     2.220 +-  0.102
 a(3)=     0.351 +-  0.104
Power-of-x coeffients a(0)+a(1)x+a(2)x^2+..., where x=r
 a(0)=     5.8113
 a(1)=     0.0676
 a(2)=     0.4215
 a(3)=     0.2373
log r(arcsec)   mu_V    mu_V(fitted)  residual   weight  data set