Test cluster PC1017 in M31, as observed with the PHAT survey (Johnson et al. 2012). Left panel is the image shown with the photometric aperture. Right panel shows the color–magnitude diagram for this same cluster. The best-fit isochrone (20 Myr, A _V = 0.9) from fitting the resolved stars is shown in black. The stars excluded in the unresolved fitting are shown in red. The unresolved method gives an age of 40 Myr and A _V = 0.42. The blue isochrone (80 Myr, A _V = 0.28 mag) that was obtained using traditional integrated light fitting is a poor fit to the resolved stars.