I got a Sigma 15mm fisheye and an 8" dome port ahead of this trip knowing that there'd be some big things to shoot - mostly wrecks and sharks. Over the few days diving I definitely learned a lot - from what settings to use when for what looks to necessary gear upgrades/purchases (I need to get a 2nd strobe and slightly longer strobe arms). That all said, I'm happy with my results - I just wish I had another week in the Caribbean to keep on working at it.
I primarily shoot macro (both on the surface and underwater), so there was a bit of a learning curve for me.
Canon 30D, Ike housing, 1x DS-125 strobe and the aforementioned Sigma 15mm FE (which I was really happy with).



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in my web gallery if you're interested.