I'm considering going on my fifth submarine ride soon, maybe next month. Last time, I only had my iPhone with me (original model), so I had really minimal photos: Atlantis Submarine by Deirdre Saoirse Moen, on Flickr Because it's a submarine, I don't need a housing. I was considering taking both cameras, keeping one lens on each. Question is: what would help me get the best shots? Not just lens-wise, but anything else I should have along?