I've wondered about this for weeks now, and now I come here to ask. I have a circular polarizer and I sometimes even use it. Upon my asking him, my dad once said: "Try it out and you will see the effect." My problem is: I don't see it. Something might be wrong with my eyes... So here goes my question: Is the blue, blue colour of the water (which reflects the sky) the effect of this filter? Nothing was done to this picture in photoshop!