Results of the FitSKIRT radiative transfer fits for two basic input models; one with analytical spiral perturbation (upper half) and one with random clumps (lower half). Left column: reference images produced by SKIRT in each of the u, g, r, i, and z bands. Middle column: corresponding fit obtained with FitSKIRT. Right column: residual images showing the relative deviation between the fit and the reference image. The colour bar at the bottom presents the scale of the deviation in the residual images.