Results for single-dust cases for cloud models A−D and $A_{\mathrm{V}}^{\text{ext}}=1$ mag. Frames a-c show the bias, the standard deviation σ of the residuals, and the MSE values. These are shown for 250 μm (red and magenta dots for Q=1 and Q=2, respectively) and for 500 μm (blue and cyan dots for Q=1 and Q=2, respectively). Frame d shows the ratio of the J-band extinction predicted by the cloud model and the median estimate, based on background stars and the extinction curve of the dust model in question. The shading corresponds to a factor of two uncertainty, and the red arrows indicate values outside the plotted range. Frame e shows the mean ratio τ(250 μm)/τ(J) in the Q=1 area, relative to the reference value τ(250 μm)/τ(J)=1.6 × 10⁻³ (red points; with τ(J) for the standard extinction curve), the shading corresponding to 1−2.3 × 10⁻³ (Juvela et al. 2015b). Frame f shows the k_ISRF values for $A_{\mathrm{V}}^{\text{ext}}=$ 1 mag fits, the shading indicating the range 60− 260. The masses of the model clouds are shown in Frame g (blue for the Q=1 and red for the Q=2 area).