The scattering and absorption efficiencies for the two dust models. The solid curves show the scattering efficiencies Q_Sca for the MWD dust (solid red line) and the OH dust (solid blue line) that have been normalised to a value of 1.0 in the V band (0.55 μm). The dotted lines are the corresponding efficiencies for absorption, Q_Abs, that have been scaled with the same factors as the Q_Sca values.