Comparison of the reconstruction of all integrated line intensities for the best fit obtained with either a homogeneous (in red) or a simple sandwich model (in green). The integrated line intensity or peak temperature are plotted as a function of the visual extinction (A_V). More precisely, the integrated line intensities (zero-order moment) or peak temperature are averaged over all the pixels whose visual extinction belongs to the [A_V − 0.5, A_V + 0.5] mag interval, where A_V is plotted on the x-axis of the panels. The lack of values for A_V ∈ [23, 24] mag results from the fact that there is no pixel in this range of A_V over the studied field of view. In each panel, the top one shows the line integrated intensity or peak intensity, while the bottom one shows the reconstruction relative error in percentage. The colored areas on the relative error panels show the standard deviation over all the pixels that belong to the 1 mag-A_V sliding window. The horizontal dashed line indicates a perfect reconstruction. While the simple sandwich model already better fit the data than the homogeneous model, the reconstruction will still be improved by refining the assumptions.