Bias $\langle (I_v^{\mathrm{MOD}}-I_v^{\mathrm{OBS}})/I_v^{\mathrm{OBS}}\rangle$ for four dust models (frames a-d). The symbols correspond to the cloud models A-D (circles, squares, triangles, and diamonds, respectively) that show here only minor differences. The x-axis label τ(J) refers to the filament (Q=1) J-band opacity, where the models are compared to the extinction derived with background stars and the Indebetouw et al. (2005) extinction curve, using either the NICER map (blue symbols) or median value of individual stars over the selected region (cyan symbols). For 160−500 μm the errors are shown for the filament (Q=1, blue symbols) and the ridge (Q=2, red symbols) regions, assuming an external extinction of $A_{\mathrm{V}}^{\text{ext}}=0.5^{\mathrm{m}}$ (open symbols) or $A_{\mathrm{V}}^{\text{ext}}=1.0^{\mathrm{m}}$ (filled symbols). The symbols are spread along the x-axis for better readability.