Cumulative luminosity distributions of all resolved point sources in the inner (upper) and outer (lower) regions of the sample galaxies. The distributions are not corrected for incompleteness or the contribution of CXB sources. The shaded areas correspond to 1σ Poissonian uncertainties. The solid lines show the predicted CXB luminosity distributions from Georgakakis et al. (2008), modified by the incompleteness function, as described in Sect. 3.1.