residuals plotted against grvs_mag. The black solid line shows the median residuals in bins of Δ(grvs_mag)=0.1 mag for stars with blue G − G_RP colours (−0.15 ≤ G − G_RP ≤ 1.2 mag; Eq. (9)), and the black dashed line the median residuals for stars with red G − G_RP colours (1.2 <  G − G_RP ≤ 1.7; Eq. (10)). The mag selection criterion to measure grvs_mag (Sect. 2.3) translates into a cut at in this diagram, resulting in the apparent rise of the median residuals at the faint end.