trigger that can change power of OCF?

Does anyone know of a trigger thats not built into a flash (i.e. 600ex) that can change the power on the fly of a compatible off camera flash?

Seeing if theres a possibility i can do a wireless flash setup with my olympus omd since they dont have a flash like a 600ex where i can control OCF power remotely.

Are you looking for something like this?

http://www.cactus-image.com/v6.html

Yongnuo YN560-TX Trigger

https://smile.amazon.c​om …=8-3&keywords=yongnuo+560

Yongnuo YN560 IV Flash

https://smile.amazon.c​om …ywords=yongnuo%​2B560&th=1

Big Frost wrote in post #18148252
Yongnuo YN560-TX Trigger

https://smile.amazon.c​om …=8-3&keywords=yongnuo+560

Yongnuo YN560 IV Flash

https://smile.amazon.c​om …ywords=yongnuo%​2B560&th=1

I didn't know they were compatible with Olympus. Good to know.

I had to research that myself at first, because I was worried they were Canon/Nikon only also. I have the same trigger, and four 560 III's and the system works flawlessly, at least for me and my needs.

wait a moment, i used the 560 before. Why didnt i think of that??

dude that cactus...ettl pass through AND can control canons flashes. wow That fits the bill really well!!

Now what to do if i make a switch to fuji....hmm

[edit] WAIT, the cactus CAN fit on any camera to control any of the listed flashes?? what?!

im seriously mind blown right now. Thats exactly what im looking for...

That Cactus is pretty impressive piece of work!