Magnification distributions (relative to the mean magnification of the image) for several assumptions regarding the contribution of a diffuse emission component to the flux in some band, which is parameterized by α (see the main text). Bold distribution curves mark α = 0.0 and α = 1.0 cases for each image parity (see the legend), with the thin curves separated by Δα = 0.2 intervals. The top panels show the emissivity profiles in log-units for three models, with their α-values denoted. Color-coding is arbitrarily but identically normalized in all panels. Note the reduced second moment of the magnification distribution function with increasing α.