NLTE corrections for Mg I, colour-coded by log g: stars are from Bergemann et al. (2017), squares are from Mashonkina (2013), triangles from Osorio & Barklem (2016), and circles from Matsuno et al. (2024). The top row compares the corrections of Osorio & Barklem (2016) assuming the same EWs as given by Bergemann et al. (2017) and Mashonkina (2013) for each Mg I line, at fixed T_eff, log g and [Fe/H] values. The bottom row compares Osorio & Barklem (2016) to the 1D and 3D NLTE corrections of Matsuno et al. (2024), only available for dwarf stars, for A(Mg)=7. The error bars represent the standard deviation of different Mg I lines (often smaller than the depicted symbols); the hatched symbols indicate corrections that are based only on one line.