VLTI/MIDI interferometry at 8–13 μm of S Ori for the example of epoch B (stellar phase 0.89, see Table 1). The panels show (upper left) the flux, (upper right) the visibility amplitude, (lower left) the corresponding UD diameter, and (lower right) the visibility amplitude as a function of spatial frequency for three averaged band passes of 8–9 μm, 10–11 μm, and 12–13 μm. The gray shade indicates the wavelength region around 9.5 μm that is affected by atmospheric absorption. The crosses with error bars denote the measured values. The solid lines indicate our best-fit model. The contributions of the stellar and dust components alone are indicated by the dotted and the dashed line, respectively.