Spatial averages of flux profiles as functions of Doppler shift Δv from the line center for the Fe i line of Fig. 9, computed treating scattering as absorption (dashed lines) and as coherent scattering (solid lines) using the 3D model with  [Fe/H]  = −3.0 (left column), the 3D model with  [Fe/H]  = −3.0 and with velocity fields set to zero (3D static model, center column) and the 1D hydrostatic MARCS model with  [Fe/H]  = −3.0 (right column). The bottom row shows normalized profiles. The 3D static model and the 1D model assume microturbulent broadening with ξ = 2.0 km s^-1; line strengths of the 1D calculations needed to be increased by  +0.7 dex to obtain similar equivalent widths (see text).