Comparison between the N(H+) + ﹩N({{\rm{H}}}^{0})﹩ + 2N(H2) hydrogen column densities derived in this study and the visual extinction derived from dust continuum observations. The lines represent the total hydrogen column density predicted for a given AV, assuming N(H)/﹩{A}_{{\rm{V}}}﹩ = 7.17 × 1021 cm−2 mag−1 for the LMC and 1.68 × 1022 cm−2 mag−1 for the SMC (Section 4.2).