Velocity dispersion derived from weak lensing as a function of optical richness (first row) and luminosity (second row) estimated with the bright red galaxies in 2 apertures, 0.5 Mpc (left column) and 1 Mpc (right column). We used only the sample of the 80 candidates defined in Sect. 5.1 (error bars on each individual measurement are omitted for clarity, see Table 2). Green points with error bars highlight the increase in σ_v with richness and luminosity after binning the SARCS lenses according to their observed richness or luminosity.