Top: optical color magnitude diagram of the X-ray detected objects in NGC 3293 based on the optical photometry from Baume et al. (2003), complemented by values from Dufton et al. (2006) for the B-type stars. The gray asterisks mark stars with known spectral type in the ACIS-I field. The X-ray sources are marked by blue squares. The solid lines in red and green show isochrones for stellar ages of 8 Myr and 10 Myr based on the PARSEC stellar models. The arrows indicate reddening vectors for A_V = 5 mag starting at the location of 10 Myr old stars with masses of 18 M_⊙, 5 M_⊙, and 2 M_⊙. The large red star marks the M1.5Iab supergiant V361 Car. Bottom: optical color magnitude diagram of the X-ray detected stars in NGC 3293 based on photometry from the VST VPHAS-DR2 survey data (blue crosses). The solid lines in red and green show isochrones for stellar ages of 8 Myr and 10 Myr based on the PARSEC stellar models, and the black dashed line indicates the main sequence. The arrows show reddening vectors for A_V = 5 mag starting at the location of 10 Myr old stars with masses of 2 M_⊙ and 1 M_⊙. The yellow-and-black dot-dashed lines show the upper and lower limits for the ranges that were used to count the number of stars in the [1–2] M_⊙ interval.