THEMIS parametrization comparison. The two panels display the same quantities as Fig. 1. On each panel, the red curve shows THEMIS, nonlinearly parametrized, that is varying the minimum cut-off radius, a_min, and the index of the power-law1 size distribution, α. The blue curve shows THEMIS, linearly parametrized, with the method described in Sect. 3.1.1. The dots on the two SED curves (panel b) represent the synthetic photometry, that is the model integrated in the filters of Table 1.