Left: Spectral synthesis fits from STARLIGHT and residuals of the nuclear spectra of three objects: (a) NGC 1672 (early spiral), (b) NGC 4697 (early type), and (c) NGC 5068 (late type). The fluxes are normalized according to the STARLIGHT normalization. Dark green lines represent the synthetic total fit provided by the STARLIGHT software and red lines correspond to the masked areas, not considered in the fitting. Right: Stellar population components of the fits on the left. The red color represents old stellar populations (∼2.5 × 10⁹ to ∼1.8 × 10¹⁰ yr), green lines correspond to middle age stellar populations (∼5.5 × 10⁷ to ∼1.4 × 10⁹ yr), and blue lines represent young stellar populations (∼1 × 10⁶ to ∼4 × 10⁷ yr) fits.