Left: SFR based on 33 GHz vs SFR based on 24 μm (following the recipe from Calzetti et al. 2007), for 3″ apertures (∼100 pc). Right: SFR based on 33 GHz vs SFR from Hα (coloured circles assuming an extinction of 1 mag; gray points show the effect of 2 mag extinction). Since the uncertainty is dominated by the effect of extinction (illustrated by the offset between coloured and gray points), we do not explicitly plot error bars for the Hα-based SFRs. In both cases, the filled circles correspond to apertures centred on HCN peaks, while the small open circles in the background show all detections (above 3σ) for Nyquist-sampled apertures across our fields of view. Downward arrows indicate upper limits (in the SFRs based on 33 GHz).