Dependence of the macroturbulent and convective velocities on spectroscopic luminosity of the star. From left to right: Observed macroturbulent velocities (left) and convective velocities for the iron (middle) and helium (right) opacity bumps predicted with MESA. The convective velocities in the middle and right panels have been interpolated on the observed positions in the HRD from Fig. 5. Symbol size and shape are the same as in Fig. 3.