What the plots represent is not clear; they do not represent spherical harmonics, which are complex.
That the two coloring schemes often produce completely different plots is puzzling. It appears that the "illuminated by light sources" option generates polar plots of absolute values of the real parts of spherical harmonics, whereas the "colored by complex phase" option generates polar plots of the absolute squares of the spherical harmonics.
No axis is shown.
The user must be sure to choose a tightly enough spaced grid to show the spherical harmonic correctly. Too small a number for the resolution gives a misleading plot.