Sea & Sea YS-D1 + Olympus XZ-1: Does TTL Work With This Combo?

[Randallr]

I posted this in the Olympus forum, but wanted to make sure it got to all the knowledgeable people, so forgive my doubling up here...

I want to upgrade the strobe I've been using with my XZ-1 from the weak Olympus UFL-1 I've been using. The Sea & Sea YS-D1 has been suggested, but the jargon is making me crazy. Sea & Sea says on its own Web site that the YS-D1 is not compatible with the XZ-1 in DS-TTL II mode, but it IS compatible in SlaveTTL mode. I'm trying to understand the difference in real world terms.

Olympus in its documentation states that my UFL-1 is operating in slave mode - I gather because it's triggered by the camera's pre-flash, so technically the strobe is acting as a slave to the camera's flash master. If that's right, does that mean the YS-D1 would work in the same way with my XZ-1, or am I just fooling myself, and I'd be forced to operate it in manual mode?

My actual goal is two-fold: to continue to use the camera and strobe in TTL mode; and to be able to use two strobes - the new, higher-powered one, and the old, weak UFL-1 - in master-slave mode. I'm pretty much convinced I can't do this with the combination of the YS-D1 and the UFL-1. But I wanted to check. Thanks in advance for your help.

 

[JackConnick]

I believe we tested this combo and it did work ok. Also the YS-D1 has two TTL modes, one is sort of a "compatibility" mode.

 

[Randallr]

Jack, can you explain the difference between the two TTL modes for me? The YS-D1 documentation says its incompatible with the XZ-1 in DS-TTL II but compatible in SlaveTTL. I don't understand the difference.

 

[EskilJ]

Basicly - the camera first fires one short shot. Based on the light reflection the camera sees from that shot, it decides the lenght (timing) of the "real" shot.
When a "TTL" (slave) strobe is mounted, it should send out the first short flash like the camera does. It should then find out how long a second flash the camera sends - relative to the first short flash. And do the same - corrected by the exposure button on the strobe.

There are several problems, though. The flash light is not linear with time - the first micro seconds are most powerfull, and the it then fades. The camera knows it's flash, but Sea&Sea doesn't. Secondly - it would be relatively easy if the first shot was always 1/10 of full power - or something fixed. Or maximum duration of flashing was a well known time. But it gets complicated to actually get the right/proportional amount of light out. And it gets hard to match full power of the internal flash with the external, so the full potential of the external is used.

I basically guess they've made a better algorithm for "guessing" how long time the strobe should light with DS-TTLII. But maybe it makes bad guesses for your camera - or you can't access the full power of your expensive strobe.