Emission line regions surrounding DELS J0411–0907. Top: the [O III] λ5007 flux map for DELS J0411–0907 after N&B quasar subtraction, with three regions of interest marked. Bottom: the integrated spectrum for the three regions (coloured lines), along with our best fit model in black. The middle panel, for Region 2, also shows the integrated spectra from the BLR quasar subtraction, in cyan, with the best fit model in grey. This region is the host of the quasar (position marked as a cyan cross in the top panel), and so the residual spectrum in this region depends heavily on the type of quasar subtraction. For Regions 1 and 3 the spectrum for both subtraction methods look equivalent, and so the BLR-subtracted spectra are not shown. For Region 2, we exclude the central nine pixels surrounding the quasar peak, as these are highly corrupted by the quasar subtraction and introduce significant noise and artefacts. This means that we slightly underestimate the total flux in this region; however, the fluxes are significantly more reliable than if these nine most corrupted spaxels were included. In Region 1, the spectral lines can be described by a single narrow Gaussian (GN), whereas in Regions 2 and 3 there is also a broader component fit with a second Gaussian (GB); these separate components can be seen as the dashed black lines for the N&B quasar subtraction, and dotted grey lines for the BLR quasar subtraction.