Color-magnitude diagrams of Gaia (upper left), SkyMapper (upper right), NSC (middle left), OGLE (middle right), M2002 (bottom left), and 2MASS (bottom right) datasets. In each diagram, different regions of BSGs (blue), YSGs (yellow), and RSGs (red) are indicated by the dashed lines. The average photometric uncertainties are indicated when available. The diagrams show a clear bimodal distribution of the BSG and RSG candidates with few YSG candidates lying between them.