NGC6342       c
 3 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)=    19.537 +-  0.160
 a(1)=     3.648 +-  0.321
 a(2)=     1.222 +-  0.259
 a(3)=     0.160 +-  0.245
 a(4)=     0.056 +-  0.158
 a(5)=     0.015 +-  0.156
Power-of-x coeffients a(0)+a(1)x+a(2)x^2+..., where x=r
 a(0)=     7.4038
 a(1)=     0.8303
 a(2)=     0.8949
 a(3)=     0.0246
 a(4)=    -0.0475
 a(5)=     0.0391
log r(arcsec)   mu_V    mu_V(fitted)  residual   weight  data set