Parametric plot of the observed intensities in the focal plane: x-axis, aperture plane optimization, y-axis, focal plane optimization. The curve is drawn for the wide spectral bandwidth without positivity constraints. From top-right to bottom-left the curve follows the increase of θ, clearly showing the concentration of light behind the occulter for the focal plane optimization. The line y = x clearly shows that the γ-curves always give better results than the Γ-curves, especially in the observation area (reported in green).