I got a circular polarizer about a couple months ago but what I realized is that I will have to keep constantly adjusting it when I'm out shooting. So I won't be able to use my hood or just shoot shoot shoot, I will have to keep adjusting the filter for every shot. Do you have to do this with a Linear polarizer or is it always "on" and you don't have to turn it to adjust the polarization. Also do linear polarizers have a "stronger" effect than cpl's? I'm mostly going to be using it to shoot cars, so there will be lost of different angles and things that I have to adjust the cpl for. Thanks a lot!