PAH EW ratios for NGC 5990. The coloured points are from spectral mapping observations and are the same as in Fig. 9. The additional black point is the staring mode spectra, which have a slit radius of approximately 1.8″. The purple point has an aperture radius of 2.5″ and has an aperture correction applied as described in Sect. 2. The black line shows a cubic spline interpolation that excludes this point. The inner purple box shows the CON selection region as defined for the staring mode spectra, and the outer box shows a larger selection region that accounts for aperture correction effects.