Eitar CIrcular Polarizing filter blurry images

[Cecilman]

Hi, I purchased the above filter from a local camera shop and was taking some photos on a bright sunny day and using auto or manual focus all pics were out of focus, when just using the uv filter they are fine. I was using the cpl filter with the uv still on the camera. Can the filter be a bad one , I think it was about $35.00 price range? Pentax K-x, with Sigma 300mm zoom. Thanks , Cecil.

[Krusty79]

I've never heard of a polarizing filter causing blurry images or interfering with the autofocus, but I guess it's possible. Even the cheap ones I have purchased did not have that problem. Can you bring it back to the shop and have them check it out?

If you do buy another, I hear B+W is the best and Hoya is good if you're on a budget.

[OsmosisStudios]

A linear polarizer can screw up autofocus and metering, but a circular shouldnt. That being said $35 for a CPL is waaaay too cheap. You're looking at around twice that for even just a decent one: good ones can easily be 3-4 times that.