Spatial distribution for M-type stars in the control field, sorted following the scheme in Fig. 10. The upper panels, from left to right, depict A_V < 0.7 stars with the same photometric properties as the lower, middle, and upper populations in Fig. 10a. Middle and lower panels are populated respectively by “field locus” and “sequence locus” stars with A_V = 0.7–1.2 (left), A_V = 1.2–1.7 (center), and A_V ≥ 1.7 (right).