Vertical reconstruction of the canopy magnetic field from the observations. The vertical cut corresponds to the blue slit indicated in panel a of Fig. 14. The colored ticks indicate the mean formation region of each spectral region indicated in Table 1: (a) blue, (b) red, (c) yellow (d) black. The z-scale has been estimated for each pixel from its atmosphere derived from an NLTE inversion assuming hydrostatic equilibrium.