Validation results of the testing samples. Similar to Fig. 4, the x axis represents distances measured by Gaia (Bailer-Jones et al. 2021), while the y axis shows distances estimated using the SBCRs in the Johnson B and V bands and the Gaia G band. The shaded blue area indicates a deviation range of ±3%. The lower subplot displays the distribution of relative errors (Δd/d_Gaia, Δd was calculated by d_SBCR − d_Gaia).