Actually, most of you are probably aware of this, but it was new to me. The G'kids were down to celebrate Christmas (early because they have to make all of the stops to get the loot. Ha!) Anyway I decided I would get a picture or two of them opening presents. I had the CP-L filter on the 18-55 lens. The TV was playing behind the wrapping paper shredders (G'kids). On a whim, I rotated the CP-L filter and the TV screen went black as if it was off. The CP-L filtered out the TV picture. It took care of the distraction in the background. I had not thought of using it for that before, but now that I know, it will probably be used more. Yes, I know the TV could have just been turned off, but in today's world, stuff like that is a necessity. Ha!