Boat photography is a bit trickier than shooting on land, but becomes more natural with practice…Framing and tracking a subject through the lens while on a boat takes some practice, as even the slightest waves can make the job very difficult, especially at higher magnifications, so start on calm water with shorter lenses, allowing a bit extra room around your subject, and progress to rougher water and longer lenses, with more tightly framed compositions. In general, you will always want to photograph from smaller boats when there is little wind, as the wind will not only kick up spray and make the water choppy, but it will move your boat around, making it difficult to photograph.
On larger boats, give yourself some time to feel how the boat moves, and see where spray is coming from, before beginning to photograph. On some big boats, you can lose your balance pretty easily while others are very smooth, so you want to know that before you take out your gear. Once you get a feel for the boat, shoot away, keeping an eye out for spray and changing weather conditions.
Photographing from a boat can add a new dimension to your photography and open up the possibility of photographing new subjects or older subjects in a new way. So the next time you venture out on a boat, consider bringing your camera gear along and seeing what you can capture.
~Kari Post from her article Have Boat, Will Photograph