Line-free continuum as derived from STARLIGHT showing the mapped area with the tessellated pattern used to extract the high signal-to-noise ratio spectra (i.e. the tiles). The reconstructed white-light image is overplotted as reference with contours in logarithmic stretching of 0.5 dex steps. The origin of coordinates here and through the paper was put at the position of the northern nucleus. North is up, east is to the left.