Spatial and temporal averages of the continuum flux distribution ⟨F^c⟩ as a function of wavelength, computed for time sequences of the 3D model atmospheres with metallicity −3.0 ≤  [Fe/H]  ≤ 0.0 (upper left to lower right), treating scattering as absorption (dashed lines) and as coherent scattering (solid lines). The upper panel of each plot shows the deviation Δ⟨F^c⟩ of the coherent scattering cases from the continuum flux distribution where scattering is treated as absorption; vertical dotted lines indicate λ = 3000 Å, 4000 Å and 5000 Å where Fe line profiles were computed. Note the Balmer jump at 3647 Å.