I got bored and have just been doing some testing on my Z330s with an oscilloscope and some photodiodes. If anyone is interested, and as curious as me... here's a rough table of the flash durations of the Z330! They're not T.1 measurements, but are pretty close.
FULL = 3300us = 0.0033sec
-0.5 = 680us = 0.000680sec
-1.0 = 534us = 0.000534sec
-1.5 = 430us = 0.000430sec
-2.0 = 348us = 0.000348sec
-2.5 = 300us = 0.000300sec
-3.0 = 257us = 0.000257sec
-3.5 = 221us = 0.000221sec
-4.0 = 186us = 0.000186sec
-4.5 = 165us = 0.000165sec
-5.0 = 130us = 0.000130sec
-5.5 = 110us = 0.000110sec
-6.0 = 97us = 0.000097sec
For an interesting comparison of output power.... with the standard -0.3 soft diffuser in place, the Z330 somewhere between -2 and -1.5 (348us-430us) settings puts out the same amount of light as a 580EXII on full power (5600us!) with the wide angle 14mm diffuser flipped down. Impressive! The colour temperature is very different too - but that is to be expected.
Bevan