I'm new here, so I want to give you all some background info first: I'm currently shooting on a Powershot G1 X Mark III with the Canon housing and a Nikonos SB-105 set to slave below the surface. Above the surface I've got a 5D mark IV. The Powershot is fun, but it ain't enough. Plus I can't get TTL to work properly with the Nikonos flash. So I'm planning on taking the 5D underwater at some point this year.
Having read through a whole bunch of stuff online, here's the conclusion I've come to, so far: I want a Nauticam housing for the 5D and a pair of TTL flashes triggered through a sync cord. Now here's the part that I just can't wrap my head around: the Nauticam housing comes with a choice of Nikonos, Ikelite or S6 bulkheads. I found a very old post stating that Canon's e-TTL requires 6 contacts, and as such only strobes connected through an S6 connector would work. Is that true? If so, I believe the only viable option for me would be Seacam's flashes. Unfortunately, at $2.5k a pop they're not exactly cheap. I'd prefer to get something like a Sea&Sea YS-D2 if I can get them to work in TTL with the Nauticam housing through a sync cord. I find that there's very little information available on this topic. Can anybody help me out here?
Thank you!
-robotr0n