Polarizer over UV or take UV off?

Just wondering if I should take the UV filter off before using a circular polarizer or do should I just put it on over the UV filter?

Don't double up filters. Take the UV off.

Thats what I thought, but why not double up filters?

You don't need the UV at all, let alone with another filter on it.

Why no doubling? Because the more glass you add, the more you degrade IQ.

Every extra glass surface you add to the front of a lens increases the risk of flare in the image or possible distortion of the image. Each filter actually has two surfaces, each of which can contribute to problems.

By using only the highest available quality multicoated filters you can minimize the potential for these problems, but stacking filters - even the best filters - is not a wise thing to do unless you need all of the filters for some creative purpose.

By the way, "IQ" in the previous post means Image Quality.

Stacking filters can also lead to image vignetting with wide angle lenses. The lens will "see" the edges of the filter and will darken the edges of the image. There is no real need for a UV filter for protections of the lens. A good lens hood does a better job and offers other benefits as well. Ditch it...

Don't stack them. I use filters mostly to protect the glass. They come off when I want to get serious.

cdifoto wrote in post #3125023
You don't need the UV at all, let alone with another filter on it.

I never thought I needed car insurence till it was broken into.

You will regret not putting on a expensive filter if and when something ever happens to the front of the lens.

Studio = No Filter
Field = Filter

Thanks to everyone for the answers, this is what I thought. I was just double checking because someone had mention stacking ND filters and I wanted to double check.

I always keep my UV on, and due to my clumsiness have badly scratched two of them, therefore I have saved myself a hell of a lot of money in lens repair bills.

Also I use the Hoya Super HMC filters which allow 99.7% of light through. Now you find me someone who can detect that 0.3% of light difference in their lens or pictures and I'll eat my hat.

If your just out taking photos for yourself, then save your lenses from damage and the hassle of screwing filters on and off dozens of times and just double up.

NDs you may need to stack to get a stronger effect. A UV filter does nothing for the picture with digital, so all stacking a polarizer on top of it does is increase the likelihood of vignetting.

never stick two filters together unless you have to. another very possible disadvantage to stacking filters is they can get stuck together, and are very difficult to get off of eachother.