Hi all, is it a good idea to put multiple filters on one lens? I have a Nikon D90 with a 18-200mm. I have a polarizer filter, a UV filter, and an NC filter. I primarily use my polarizer, the NC I use when there is no other filter, and I rarely use my UV. Would it be practical to put on my polarizer first, then top it off with the NC? I use the NC as a 'shield' more than anything.