Luminosity functions of galaxies in the low‐﹩L_{\mathrm{X}\,}﹩ (thick solid line) and high‐﹩L_{\mathrm{X}\,}﹩ (thick dotted line) clusters after field correction, both renormalized to the average number of galaxies per cluster in the high‐﹩L_{\mathrm{X}\,}﹩ sample. The error bars include the uncertainty in the background correction; the field component subtracted from the low‐﹩L_{\mathrm{X}\,}﹩ and high‐﹩L_{\mathrm{X}\,}﹩ samples are shown as the thin solid and thin dotted lines, respectively.