Vertical B_z (middle column) and horizontal B_y component (right column) of the magnetic field of the last snapshot of the SSD time series of the G2V (top pair of rows), K0V (middle), and M2V (bottom) stars. The vertical velocity (left column) is shown again to facilitate the visualisation of the magnetic fields in terms of the velocity structure. The values of the magnetic fields shown in the colour maps are indicated by the corresponding colour bars (all of them clipped at |B| = 1 kG). The upper panel of each pair of rows shows the surface at τ = 1 ; the lower panel shows a vertical cut at the middle of the snapshot. The location of the iso-τ surface and the vertical cut are shown as black solid curves. Red circles show the location of flux concentrations that produce magnetic bright points (see Fig. 5).