Standard deviations in colors for GALAXY photometry vs. magnitude and surface 
  brightness.

Galaxies:  Sigma1 (Color Index) vs. V Magnitude (Figure 12):

B-V:  y = Sigma1 (B-V), x = V Magnitude
  y = 3.5384e-6*exp(0.71519*x)

U-B:  y = Sigma1 (U-B), x = V Magnitude
  y = 0.00028062*exp(0.40149*x)

V-R:  y = Sigma1 (V-R), x = V Magnitude
  y = 1.8786e-5*exp(0.58529*x)

V-I:  y = Sigma1 (V-I), x = V Magnitude
  y = 0.00011801*exp(0.49742*x)

-----

Galaxies:  Sigma1 (Color Index) vs. Surface Brightness, V magnitudes
  (Figure 13):

B-V:  y = Sigma1 (B-V), x = Surface Brightness, V magnitudes
  y = 2.3206e-6*exp(0.65578*x)

U-B:  y = Sigma1 (U-B), x = Surface Brightness, V magnitudes
  y = 8.4851e-5*exp(0.43955*x)

V-R:  y = Sigma1 (V-R), x = Surface Brightness, V magnitudes
  y = 2.0277e-5*exp(0.5022*x)

V-I:  y = Sigma1 (V-I), x = Surface Brightness, V magnitudes
  y = 3.9451e-5*exp(0.51307*x)

******************************************************************************

Standard deviations in colors for photometry of STARS vs. magnitude 
  (Figure 14):

B-V:  y = Sigma1 (B-V), x = V Magnitude
  y = 0.00015713*exp(0.37427*x)

U-B:  y = Sigma1 (U-B), x = V Magnitude
  y = 0.00015324*exp(0.42796*x)

V-R:  y = Sigma1 (V-R), x = V Magnitude
  y = 6.3773e-5*exp(0.42697*x)

V-I:  y = Sigma1 (V-I), x = V Magnitude
  y = 0.00015125*exp(0.40345*x)