Consistency tests for chemical abundances derived with SP_Ace. All plots show the difference between the derived [Fe/H] and various changes to the spectrum as described in the text: a) with cosmic ray regions flagged out; b) with sky emission regions flagged out; c) adopting the initial resolution of R = 28 000; d) Δlog  g = 0.3; e) ΔT_eff = 200 K; f) all five orders analyzed separately (orders 52, 53, 54, 55, 56: circle, diamond, square, left-handed triangle, right-handed triangle). Given the limited wavelength range and the limited chemical information, not every individual order in each spectrum provides a result. Additionally, some orders in some stars are more affected by the different pixel masks and hence might show larger offsets.