(a) NGC 524 H α peak flux map, overlaid with the identified emission-line regions (grey contours) and the locations of the identified emission local maxima (crosses; colour-coded according to the ionization mechanism identified in panel b). The two bright central regions are highlighted as stars. (b) Emission-line ratio diagnostic diagram of Law et al. (2021), with the identified emission-line region data points overlaid (colour-coded according to the ionization mechanism). Again, the two bright central regions of panel (a) are highlighted as stars. (c) Extinction (A_v) of each emission-line region as a function of galactocentric distance. (d) Extinction-corrected H α surface brightness map.