This new webcast, prepared by Laborelec for Leonardo ENERGY, discusses the basic principles of artificial lighting, light sources and armatures in relation to energy efficiency in lighting systems.
View webcast (14 minutes)
Unfortunately the ballast losses given in slide 17 conflict with data given in another place of the same website. In Fig 8.2 it says there that the loss in a B1 (magnetic) ballast is much less than in an A3 (electronic) ballast.
Also, it raises doubts there that the improvement of efficiency at high frequency is as high as the difference between the lamp power ratings for HF and 50Hz. Rather, it claims the light output measured on a 58W lamp is lower when operated on HF (with electronic ballast).
In this webcast, 'armature' is used to mean 'luminaire'
On slide 19 it would be useful to plot efficiency and CRI for each type of lamp.