Mass-weighted SFHs for NGC 1433 from collapsed spectra of the MUSE original data, ND data, and representative MD data, as illustrated in Fig. 2. The y-axis corresponds to the mass formed, in solar masses, for each age bin and the x-axis to the age in Gyr, that is, the look-back time. The original data are shown with a solid red line, the subtracted data with a dashed blue line, and the representative spectrum with the dot-dashed green line. The lines are the SFHs derived from the data, while the shaded regions are results from 100 Monte Carlo runs. In the bottom panel we display ND/MD in black, and highlighted with an orange circle is the age where ND/MD rises above one for the first time, together with the statistical uncertainty: Gyr.