SFR measured from the STARLIGHT modelling of the SDSS spectra against the total stellar mass of the host galaxies (Pierce et al. 2023). The colour scale shows the ratio of the physical size on the galaxy covered by the SDSS fibre against the r-band Petrosian diameter. The black solid line shows the SF main sequence (MS) defined in Saintonge et al. (2016) and the dashed black lines the range of SFR that is considered to cover the MS (±0.4 dex).