Comparison of the Hα and 21 μm emission for NGC 0628. Top-left: 21 μm surface brightness image obtained using the F2100W filter on MIRI, convolved to the MUSE copt resolution (0.92″). Top-right: map of the Hα surface brightness from MUSE (Emsellem et al. 2022). White contours enclose regions of bright 21 μm emission (I₂₁ > 10^40.5 erg s⁻¹ kpc⁻²). Bottom-left: same as top-left, but with the boundaries of the optically selected H II regions from Groves et al. (2023) in blue and the 21 μm sources which do not overlap with optical H II regions from Hassani et al. (2023) in red. Bottom-right: ratio map of the Hα to F2100W surface brightness. Red contours are bright Hα regions, I_Hα > 10^38.8 erg s⁻¹ kpc⁻². White regions within the mapped area represent areas with S/N < 3 in F2100W. The boundaries of the MUSE (solid black) and MIRI (dashed black) mosaics are shown to aid in visualising the data overlap.