I want to take some waterski action photos on a lake in late summer afternoon. The sunset angle ranges from 30' to 15' (5:30 to 7:00pm). Luckily the sun sets behind me and the lakeside so there isn't going to be much of a direct sunlight glare problem. However the water splashes and the lake surface itself will generate some glares and reflections. Should I use a polarizer? or another type of filter? I will likely be using the Panny 45-175mm f4-5.6.