Can someone advise me what to look for when buying a circular polarizing filter? Im not sure what size (thread size) to get, most of all. I have a 18-55mm lens, does that mean I should get the 55mm size filter? I also dont know what "drop in size" or "Rear and Bayonet Mounts" are. I also dont know the difference between "Circular Polarizers", "Circular Hybrid Polarizers", and "digital circular polarizers". Furthermore, I have no clue on how to put one on...i know how lame that is! Can you use a polarizing filter with a lens hood...or is that overdoing it? All this technical stuffis making my head spin! Any help will be greatly appreciated! P.S. I hear Hoya is a good brand?