Disc gas density, gas-to-dust ratio, SED, and localization of the continuum emission for the fixed vertical structure disc model. The disc is gas-rich above the mid-plane and gas-poor in the mid-plane. For clarity a couple of observed photometric points are not shown in the SED. The lower-right panel shows the cumulative continuum emission for 15% and 85% for each wavelength. The continuum emission for wavelengths greater than 500 μm comes from the outer disc (R > 100 AU).