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I'm having a problem with a polarizing filter that's I've used for years.

I have a Nikon D7000 w/18-200mm lens. I keep a UV filter on the lens, and on occasion I add a circular polarizer, which just recently began giving me images with exactly the opposite result that I'd expect.

Today for instance, I shot some beach scenes and later a waterfall against the blue sky. As a test due to some failed shots earlier in the week I tested a theory. I shot a few on a tripod with the polarizer. I turned it until the sky was deep blue and the glare was off the water. Looked great in the viewfinder.

I get home and the images look like I had the polarizer set 180 degrees out. They're hazy, soft and almost out of focus.

Now the test I mentioned was that I changed nothing but taking the filter off the lens and the shots look great. Clear, vibrant and crisp.

Compare both images: enter image description here enter image description here

So I ask, is it something I'm doing, Never had this issue until recently. Do polarizing filters go bad?

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    How are you focusing? Does your lens rotate the front threads when it autofocuses? – Michael C May 4 '15 at 2:30
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    Why are you using a UV filter? Your D7000 has a UV filter in the filter stack immediately in front of the sensor. – Michael C May 4 '15 at 2:32
  • I'm using auto focus. No the threads do not rotate on this lens, good question though. The camera was on a tripod, I adjusted the filter and fired the shot with a remote IR trigger. I use a UV filter on all my lenses mostly to protect the front element. Again, I've shot with this exact setup many times. In this case the glare on the water is terrible the sky is hazy and the color is desaturated with low contrast. I'm on vacation at this exact moment but on Tues I can throw some samples up online to show you. – Aaron Lewis Photography May 4 '15 at 2:55
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    @dpollitt Interesting. I know that every layer of glass in front of the element decreases and degrades light to some degree. BUt again, this is a new issue. I guess what I have to do try shooting without the UV filter in the picture. Problem now is I'm leaving tomorrow morning to head home :( I guess I can find a way to test that at home. – Aaron Lewis Photography May 4 '15 at 3:06
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    If a multi-layer filter came apart the impact would at the very least involve a massive increase in flare, due to the two new glass surfaces that have no anti-reflective coatings. – thomasrutter May 7 '15 at 4:16
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Every bit of glass you place in front of the lens will cause flare. In general, expensive filters cause less flare than cheap ones, and fewer filters cause less flare than more filters.

When you think lens flare, you may think of the circles or shapes that appear in frame as reflections of the sun, but lens flare refers to all unwanted light coming from reflections inside the lens assembly, and can manifest as an overall "haze" or reduction in contrast (exactly like in your example image).

  • Make sure your filters are all multi-coated. I'm referring to the anti-reflective coatings. Uncoated filters will cause lots of flare (whole orders of magnitude more flare) while single-coated will still cause noticeably more than multi-coated ones.

    Note: all the elements in your lens itself will be multi-coated on any surface exposed to air. You lose the benefit of multi-coating if you add just one filter/piece of glass in front of it all that isn't multi-coated.

  • Make sure the filters are clean. Any dirt or oily smears on them will increase flare or haze.

  • For goodness sake, remove the UV filter when putting on the polariser. No need to have more flare than you absolutely need. I'd advise not using a UV filter at all, they are good for nothing other than increasing flare. That, however, seems to be a controversial statement to some photographers, so if you are religiously opposed to shooting without a UV filter then by all means make sure it's a good one and that you take it off when you add a different filter.

  • Good answer. However in my opinion the only reason to use UV filter is to protect the lens front element, not to remove more UV (lenses are already made of glass and it filters the UV already). Breaking or scratching an UV filter is expensive (if you take MC) but still less than the front element of the lens itself which could be as much as a new lens price. After it's just a matter of personal usage and balance between the cost of the lens and the risk to scratch it. – рüффп Oct 11 '16 at 22:52
  • An I personally used an UV filter + Circular polarizer on a Nikkor 16-85mm and found no similar issues with this setup. Filters were from Nikon as well (or perhaps just the polarizer a B+W). But for sure all are multi-coated. – рüффп Oct 11 '16 at 22:55

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