Weather sealing for professional level cameras is pretty good:
Built to shoot in rain grab with wet hands etc. Salt does add a new problem, and i certainly wouldnt wet them when you dont have to but I used a Canon 7d in a kayak, never had a problem, but i keep a towel in thr pelican to wipe the hands before the shooting. I got the photo bug bad, and am about to upgrade to fullframe myself; even more weatherproof than my current model semi-pro.
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