Kiel diagram with effective temperature T_eff and surface gravity log g for the complete GALAH+TGAS overlap. The spectroscopic parameters are results of the analysis in Sect. 3.1. Colour indicates the relative parallax error. Most precise parallaxes are measured for the cool main sequence stars and the parallax precision decreases both towards the turn-off sequence and even more drastically towards evolved giants, which are the most distant stars in the sample. Dotted and dashed black lines indicate the limits to neglect hot stars (T_eff >  6900 K) and giants (T_eff <  5500 K and log g <  3.8 dex) for the subsequent analysis, respectively. See text for details on the exclusion of stars.