Contrast-separation diagram for V-band reflectance parameters (no polarization information added for clarity reasons) showing the famous HR 8799 exoplanetary system with its four confirmed candidates. The planet e was assumed to be the same size as the three other planets (1.2R_Jupiter). All four planets but planet d follow a “back and forth” locus because of their null eccentricity. Despite their large reflecting area, the contrast ratios are extremely low because of their distance to the host star.