Scale factor vs. effective temperature for the post-MS stars of the HARPS sample. The relation for the post-MS stars is fitted with a cubic polynomial (red line, Eq. (3)) to the binned scale factors (red bars indicate the median absolute deviation), while the MS results (gray, dashed line for the fitted relation S_HARPS,MS (T_eff), gray markers for individual stars hotter than 4000 K; Paper I) are included as reference. The surface gravity for each post-MS star (based on MIST fits) is color coded. The marker shapes correspond to the evolutionary phases according to MIST: sub- or red giant (triangle), core Helium burning (squares), and asymptotic giant (diamonds).