Overlap luminosities. Left: comparison between the luminosity L₅₀₀ for each detection of an MCXC-II cluster, computed from the primary or overlapping catalogue parameters, and their weighted mean value. Overlaps between 400SD and 160SD clusters have been excluded since the data are almost identical. Symbols and colours, as labelled in the figure, identify the input catalogue (primary or secondary). Right: difference in luminosity L₅₀₀, in dex (top panel) and relative to the errors (bottom panel). Full horizontal line: median value; the dashed, dotted and dash-dotted horizontal lines marked the 68%, 90% and 95% dispersion around the median, respectively.