Comparison of observed (first row) and modelled (other rows) 1.25–3.4 μm surface brightness. The second row corresponds to J13 dust, W = 1, and no sky background (I_bg = 0). The effects of sky background are included in the other cases (J13 dust with W = 1 and W = 1.7, and AMMI with W = 1, and the THEMIS model with three dust components). Frame f indicates the areas used for correlation analysis, the larger area shown with a thin cyan line (excluding the sources B1–B3) and the smaller area with a thick cyan line. The yellow circles indicate the reference region used for setting a common zero level. Black contours are drawn at 1.5 times the maximum of the colour scale. The colour scale is the same for all models but different for observations.