Comparison between 1D LTE and 1D NLTE Mg determination. Top panels: difference between 1D LTE and 1D NLTE abundance as function of atmospheric parameters, abundance, and REW for the line at 5528 Å. The rightmost panel displays an exponential function fitted to the dispersion, its coefficients are given in the plot. The shade areas cover three regions of REW: consistent (R E W<−4.95), saturated (−4.95 ≤ R E W<−4.80 ), and over-saturated ( R E W>−4.8 ) (see main text for explanation). Dispersions of the points around the fitted function are 0.0072 (consistent region), 0.0399 (saturated region), and 0.0397 dex (over-saturated region). Bottom panel: similar to the top panel, but for the line at 5511 Å.