Comparison of true luminosity distribution and MGE-predicted luminosity distribution for Au-23-85-50. The true luminosity distribution is derived from the stellar particles in simulations by assuming a constant mass-to-light ratio (M_⋆/L)_T = 2. Left panels: from top to bottom, the panels show the normalised true luminosity distribution Σ_true of Au-23 in the intrinsic x-y, x-z, and y-z planes. Middle panels: the corresponding MGE-predicted luminosity distribution Σ_mge, which is deprojected from 2D MGE under the true viewing angles (θ, φ) = (θ_T, φ_T) = (85° ,50° ). Right panels: the residuals between the true and the MGE-predicted luminosity distribution (Σ_true − Σ_mge)/Σ_true. The value in each panel represents the average absolute value of the residuals.