Mon 21-Apr-08 12:42 AM | edited Mon 21-Apr-08 12:45 AM by Wayne
The salesman was correct if you have your triggering camera flash in TTL mode. Automatic flash on digital cameras do use preflash, which do trigger manual optical slaves. Screws things up big time.
You are correct if you have your triggering camera flash in Manual flash mode (to suppress preflash). So that nothing is in auto TTL mode.
That is the only good answer, but you could also use FV Lock with TTL flash, for which the first metering preflash (trying to meter) would trigger the manual slaves, and then the subsequent shutter trigger would work (would trigger them again, but without preflash again, assuming given time to recycle first). That is a pretty huge kludge however, which makes little sense. Why would you consider trying to use TTL flash with manual flashes that cannot do it? If using manual flashes, then just put everything in manual mode as it ought to be.