Upper panels: brightness spectra of the quiet Sun (black curves), faculae (red curves), spot penumbra (blue curves) and umbra (magenta curve, only plotted in the upper left panel). Lower panels: facular (red curves) and penumbral (blue curves) brightness contrasts with respect to the quiet Sun. The dotted curves are calculated taking the spectral lines (full linelist) into account. The solid curves are calculated by putting the opacity in the molecular (middle panels) and in all spectral lines (right panels) to zero. To facilitate the comparison between different spectra and contrasts the dotted curves are plotted in all three panels. The two vertical dotted lines in the left panel constrain the spectral interval shown in the middle panels.