Olympus was, as far as I know, the first to introduce a "long duration" electronic flash. It fires a burst of individual flashes for a period of 1/60th of a second - the time it takes for both curtains to move across the film frame. In the OM-4T, that would work at a shutter "slit-speed" of 1/2000th second. Unfortunately all that "stobing" takes a lot of power, so the guide number of each individual burst is really low.Originally Posted by rbarker
The "Synchronization" speed, where the film is totally open to the image, is also the speed where the shutter defaults when the batteries fail or are removed ... without electricity it is "mechanical" ... in the case of my Olympus OM-4, 1/60th second.