Cross-correlation data obtained with stacking using the background sample derived from the WISE catalogue and the foreground lens sample from the ZOU cluster catalogue. The purple data make use of the BCG coordinates to determine the clusters positions. The pink data were obtained with the cluster positions given by the peak coordinates of the luminosity distribution. Left panel: The case with npix = 400, a pixel size of 0.5 arcsec, and σ = 2.4 arcsec. Right panel: The case with npix = 2000, a pixel size of 0.05 arcsec, and σ = 0.3 arcsec.