Number counts are the results of integrating over intrinsic luminosity and distance.
Early faint galaxy counts showed a marked number excess over standard models incorporating -corrections but neglecting evolutionary effects, and an overall blueing trend. Shanks et al. Koo koo86 presented UBVI counts and color distributions of 10000 galaxies to B 24. Galaxies fainter than B 20 also had progressively more of an ultraviolet excess eventually exceeding that of Galactic subdwarfs. Tyson tyson88 conducted a very deep multicolor imaging survey of 25000 galaxies that revealed strong evidence for color and luminosity evolution.