Departure coefficients, b, for the levels of Fe i and Fe ii as a function of log τ₅₀₀₀ in the model atmospheres 5777/4.44/0 (left column) and 4600/1.60/−2.50 (right column) from the calculations with our final model atom of iron (top row) and the reduced model atom, which ignores the predicted levels of Fe i. Every fifth of the first 60 levels of Fe i is shown. They are quoted in the bottom right part of each panel. All remaining higher levels of Fe i are plotted by dotted curves. For Fe ii we show every fifth of the first 60 levels. They are quoted in the top right part of each panel. The letters z, y, x, ... are used to denote the odd parity terms and a, b, c, ... for the even parity terms. To distinguish Fe i and Fe ii levels, note that b < 1 for each Fe i level outside log τ₅₀₀₀ = 0 in the solar metallicity model and log τ₅₀₀₀ = 0.4 in the metal-poor one. An exception are the highest levels in the layers with log τ₅₀₀₀ around −2.5 in the model 4600/1.60/−2.50. For Fe ii, b ≥ 1 inside log τ₅₀₀₀ = −2 in both model atmospheres. S_H = 0.1 throughout.