Relation of line-of-sight dust mass surface density with V-band attenuation derived by the BD (left panel), attenuation of the old stars by the SED fitting (middle panel) and attenuation of the young stars also derived by CIGALE (right panel). Uncertainties in both axes are shown in grey. The dust mass surface density estimated under the assumption of a foreground screen dust model is plotted with a solid line. The dotted and dash-dotted curves show the results of the slab and sandwich models, respectively: those in the left panel are for the A_V, BD–Σ_dust relation, those in the central and right panel for A_V–Σ_dust. The best fit of Kreckel et al. (2013) is plotted with a dashed line in the left panel.