H-R diagram of our population synthesis using the initial distributions discussed in Sect. 3.2. Regions subject to selection effects (Sect. 3.3) are highlighted as: gray – stars too faint for the observed magnitude cutoff; green – stars with T_eff    >    35   kK; red – stars with low surface gravities (log g    < 3.2); yellow – remaining stars. Results from Hunter et al. (2009a) are over-plotted (blue: stars in N11; black: NGC 2004; with their shapes indicating their surface gravities). Radial velocity variables and Be-stars that are indicated by crosses and diamonds, respectively. Evolutionary tracks of 10 M_⊙, 20 M_⊙ and 30 M_⊙ of non-rotating models are shown for orientation.