Head-on viewed surface brightness profiles for the specific case of the HR 4796A disc. The parent body ring is located between 67 and 75 AU. For each case, the planet is placed as close as possible to the parent body ring (i.e., so that the outer limit of the stability region coincides with the ring’s outer edge). The solid line indicates the deprojected observed profile, derived from Schneider et al. (2009). The horizontal line delineates approximately the part (above this line) of the profile with a dynamical range of 10. As in Lagrange et al. (2012), we show, for each case, the radial cut at the “best” position angle, i.e., the one providing the best match to the observed profile. Note that the goal of these runs is to fit the outer profile, not the inner one, which should probably be shaped by other mechanisms (see discussion in Lagrange et al. 2012), so that not too much physical significance should be given to the profile interior to the ring’s inner edge.