Astrometric HRDs with different x-axes. From left to right: B–V, V–I and log(T_eff). The colored lines represent HB and RGB evolutionary tracks with metallicity Z = 0.0180 and masses of 1 M_⊙ (blue), 2 M_⊙ (green), 3 M_⊙ (violet), 4 M_⊙ (gray) and 5 M_⊙ (turquois). Bold black parts of the evolutionary track show the region that is affected by the degeneracy in B–V due to the differential absorption of TiO bands in M giants, while orange triangles are stars that are in their 1σ range affected by this degeneracy. The astrometric HRDs with V–I or effective temperature plotted on the x-axis show that no giant star of our sample can be attributed to the M-giant region of the evolutionary tracks.