MT Shooter wrote:
Primarily they affect AF systems. Many cameras also experience metering problems also. I use an OLD Linear on my F5 and D90 Nikons with no meter problems, but the AF goes nuts searching with it, I only use it when manually focusing as it gives me better overall results than my Circular Polarizer does.
I can vouch for the circular polarizer messing with the AF. I was at an air show last summer. Right before the F-15 was to perform I borrowed a circular polarizer from my brother to put on my Canon 70-300mm IS. I took about 40 shots of the F-15 performing - every single shot was out of focus and soft - unusable. After removing the polarizer all the subsequent shots were once again ok. So needless to say, I won't be shooting moving targets with a polarizer on this lens again. Lesson learned - the hard way.