Joint 2D posterior probability distribution for the parameters of the composite mock (presented in Sect. 3.2.4), with kinematic data having a signal-to-noise of 15 in the brightest pixel and binned to have a signal-to-noise of 30 in each bin (shown in Fig. 11). The different contours in the 2D plots indicate, respectively, the 1σ, 2σ and 3σ ranges. Parameters shown are those where the improvement on the constraints coming from the combination of lensing and dynamics (LD in red contours) is more prominent as compared to lensing only (L in grey contours). These parameters are the source centroid x_c, s, y_c, s, the anisotropy β, the position angle of the lens dark matter profile , its Einstein radius , and the shear parameters γ_ext, ∞ and ϕ_ext. In the diagonal are shown the 1D histograms of the corresponding parameter on the x-axis. The input values are marked with a yellow cross.