Mass-loss rates versus different temperature scales for a series of dynamically consistent atmosphere models with log L/L_⊙ = 5.7, M = 20 M_⊙, and Х_H = 0: the thick red dashed line denotes the effective temperatures defined at a Rosseland optical depth of τ_R = 2/3, while the green solid line and the blue dashed-dotted line denote the effective temperatures referring to τ_crit and τ_R,cort = 20, respectively. The green dotted line on the right denotes the (electron) temperature at the critical point. Curves in lighter colors reflect models using the simple integration treatment suppressing negative velocity gradients (cf. Sect. 2). The black dashed line shows the hydrodynamic structure solutions by Grassitelli et al. (2018).