Upper panel: deviations from the microclumping approximation of equivalent widths of synthetic H_α  line profiles versus mass-loss rate (see text). Clumping starts at 3_cl = 0.24 and 0.06 (r_cl = 1.3 and 1.05), respectively, as indicated in the figure. Lower panel: H_α line profiles as calculated by stochastic, analytic, and microclumped models with f_cl=9 and Ṁ = 10  ×  10^-6   M_⊙/yr, and the rest of the stellar and wind parameters as for λ Cep. Clumping for all models starts at 3_cl = 0.24.