Stuart, you are correct, I momentarily confused myself, yes, use the pre-flash selection switch per the instruction manual to select the no pre-flash mode on the strobe. Set you camera for no pre-flash in the internal menu for no pre-flash in Auto (Av/Tv). This will allow you to run between Manual strobe and Manual camera or Auto strobe and Auto camera or Manual camera and Auto strobe modes. Selecting Program will probably default your camera to pre-flash so you will need to reset your Z240 if using it in Auto mode but in s-TTL mode the strobe will also default to pre-flash (no need to select on the strobe with the switch).
Yes, I think you understand. I keep thinking for some reason the pre-flash switch on the Z is a rotary switch because you push it and then turn it to lock it, my memory failing me on that, sorry for the confusion.
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