Abundance measurement for VFTS 466, a relatively high S/N source. Not all lines used are shown. Left panels: the observed spectrum is shown in blue and the best model fit in black. The nitrogen abundance of the best model resulted from combining all utilised lines and is given by the ε_N in the figure title. The selection of the fit region is displayed in red. Middle panels: zoom in on the fitted region, with the best fit Gaussian profile in red. Right panels: theoretical W_eq values as a function of ε_N (horizontal axis) are shown in black. Measured W_eq and interpolated ε_N are in red and blue, respectively. Dashed red lines indicate the measurement error and dashed blue lines the corresponding uncertainty in the best fit value.