Extended Zoom Mode
Metz auto-zoom flashes have a unique feature: they can be set so they use one zoom step wider than strictly required to cover the field of view of the current lens focal length. This provides a more diffuse light with more reflections bounced from out-of-frame — nice, when you don't need all the focused power anyway.
Of course, you can do this manually on the AF 36-4, or on any flash in manual-zoom mode, but then you must remember to keep up as focal length changes.
Note that the ST version of the Sigma EF-530DG lacks a manual zoom mode entirely.
