Cosmological log N − log S for clusters of galaxies. The black discrete curve shows the confidence interval resulting from measured source detection flux errors and an additional on the number count from this work. A comparison to comparable surveys is made. The curves show the model from Rosati et al. (2002) for no evolution (dashed). The dot-dashed and dotted lines show the measured ROSAT brightest cluster sample (BCS, Ebeling et al. 1998) clusters and their extrapolation, respectively. The discrete lines display the findings from COSMOS (solid) (Finoguenov et al. 2007), SXDF (dashed) (Finoguenov et al. 2010), and XMM-BCS (dotted) (Šuhada et al. 2012).