BPT diagram for W2246f at the top along with the [S II] (middle) and [O I] diagnostic diagrams on the left. The brown curves represent the maximum starburst line of Kewley et al. (2001), the dashed brown lines represent the separation between Seyferts and LINERs from Kewley et al. (2006), and the blue curve in the top plot represents the pure star-forming line of Kauffmann et al. (2003). The error bar above the legend represents the median uncertainties in the line ratios. The uncertainties in the BPT diagram at the top have been separated according to the binned spectra that lie in the star-forming, composite, and AGN regions of the diagram, and use the same colour scheme. The maps on the right demonstrate the distribution of the bins in each region of the diagnostic diagrams over the galaxy.