Observed color−magnitude relation of spectroscopic members of MACS1206. Each galaxy has been color-coded according to its mass. In the lower panel we contrast our sample (yellow density contours) to the color distribution of Subaru Suprime-Cam detections in the same field of view and at similar redshift range (blue filled density contours). This allows a rough visualization of completeness for our sample. We provide more detailed 2D completeness maps in the Appendix.