From left to right: maps of the line centre (λ = 8542.13 Å) Stokes I, Q/I, and U/I signals. The V/I signals are shown at the near-blue wing (λ = 8542 Å) of the line. We show the polarisation signals resulting from the scattering polarisation and the Hanle effect (top row), the Zeeman effect (middle row), and the joint action of the scattering polarisation and the Hanle and Zeeman effects (bottom row). The arrows point to the pixels with representative Stokes profiles, shown in Fig. 6.