Is the preflash in the camera or in the Symbiosis (sorry if the question seems stupid, but I don't know)?
The flash does not have TTL mode, so I can't say.
I'll look into preflash - thanks :-)
I think symbiosis completely mimics the on-board flash of the camera, which has a pre-flash (for metering) and the main flash. I think you can't put your on-board small flash into complete manual mode (single flash) but I have to check. I don't have the camera with right now.