Hi David, yes I've read that many have tried and Canon's eTTL protocol has so far proven notoriously hard to crack. I'm using manual flash with electrical sync cables on my NA5DMkIII housing but was looking for something that'll work with fiber-optic cables instead. If you work out a flash trigger (LED based I presume?) for the 5D MkIII I'd be interested!
Don't know how I missed this.
yes I have successfully installed LED trigger for any housing. Working on a design for an optiical bulkhead although the new nauticam ones seem to fit my LEDs.
These will allow fairly quick sync flash. I am still waiting for my programmer to get the little LED buggers to sync above 1/200