Synthetic model-atmosphere spectra for the cluster members qF240 (WN10h) and qF241 (WN11h) computed for two differing assumed interstellar reddening laws, illustrating the dramatic dependence of bolometric luminosity on this choice. HST photometry employed are from Table A.1. The black lines reflect the model spectra reddened by α = 2.028 and 2.348, which results in A_ks = 2.346 and 1.751, respectively. The blue lines follow Moneti’s law with A_ks = 3.459 and 3.283 respectively. Transmission curves for the filters used for the fit are shown in green (broadband) and pink (narrowband), and symbols are plotted for each magnitude measurement to show the goodness of fit: orange diamonds for the α-model and pink stars for the Moneti model. The x-axis position of each symbol corresponds to the classical λ₀ of the filter at which the zero-point flux is defined. The y-axis position coincides with its corresponding model curve if the observed magnitude matches the magnitude of the reddened model.