G_BP − G′ vs. G′−G_RP diagram that includes all stars with 2MASS counterparts, good-quality photometry, and K <  9 mag. The intensity scale is logarithmic. The lines with symbols mark the extinction trajectories of a red giant with G_phot >  10.87 mag using the family of extinction laws of Maíz Apellániz et al. (2014; symbols are spaced by ΔE(4405 − 5495)=0.1 mag and reach to E(4405 − 5495)=5.0 mag) combined in six ways by selecting (a) R₅₄₉₅ = 3 (normal extinction) or R₅₄₉₅ = 5 (H II region extinction) and (b) MAW, REV, or WEI sensitivity curves. See the text for more details.