Comparison of cluster luminosity functions in the K_S passband. built for different samples (MWSC and COCD) and different completeness approaches. Left panel: CLFs based on the magnitude-limited approach for the COCD cluster sample (red filled histogram) and for the MWSC cluster sample (green hatched histogram). Right panel: CLFs for the MWSC cluster sample based on two different techniques, the distance-limited approach (red filled histogram) and the magnitude-limited approach (green hatched histogram). The Poisson errors are shown with vertical bars. The thick lines mark linear fits of the MWSC CLFs in the magnitude range (I(M_KS) = −8–−4). The extrapolation of the fits outside this magnitude range is shown by the dashed lines.