I bought a circular polarizer today.

And I don't get it.
Is it really supposed to make the sky more blue? Because I don't think it does. I only saw the pictures in the LCD though because I'm on a trip...

I read this in a website,
"Lenses with rotating front elements will mess up your polarizing filter's rotation. If your lens has a rotating front element, you should adjust the polarizing filter after you've set the focus."

is this true? Mine has a rotating front element. How does it work?

The polarizer rotates in its mount. You need to turn the filter until you get the maximum effect. And if the front of your lens rotates as you focus, after you've adjusted the filter, that changes the filter allignment as well. So you need to readjust the filter.

But, it's pretty much ineffective if you're looking toward the sun and most effective if you're looking at right angles to the sun. So you won't see the effect in all directions. Also, it won't help on an overcast day. So it's not a magic pill that gives you blue skies regardless.

You should be able to see the effect in the viewfinder, to a degree, as you rotate the CPL.

So when I turn the filter I should see the difference in viewfinder?

EDIT: I didn't see the post above, sorry! Thanks guys, but I didn't see any difference in the viewfinder that's why I asked. I guess it must be the angle.

cryforashadow wrote in post #6038124
So when I turn the filter I should see the difference in viewfinder?

EDIT: I didn't see the post above, sorry! Thanks guys, but I didn't see any difference in the viewfinder that's why I asked. I guess it must be the angle.

Do you have an LCD monitor? If so take the CPL off the lens and hold it between you and your monitor. Turn it and it should turn black and then most clear as you are turning it.

With it on your lens, point the lens at a building with glass windows where you can see reflections in the windows. Focus and then turn the CPL, you should see the reflections disappear in the viewfinder.

The bluer skies may be a bit tougher to notice. But point your camera in various directions, stopping and adjusting the CPL. You can also do all this with it off of the lens, holding it to your eye. That will make it more apparent.

The angles matter, as Jon stated. CPL's are great tools once you get them figured out.

Here's a link to some images that were taken with a 70-200 f/4L WITHOUT CPL and a 24-70 f/2.8 L WITH a CPL.

You can also see for some of the images taken with the 24-70 that the polarizing effect wasn't always the same, which was due to where the sun was in the sky in relation to what I was shooting (i.e., as Jon stated above).

http://bobanderson.smu​gmug.com …002_72Gce#24608​0504_eU23F

Sorry that the images are so cr@ppy

Another effect that a polarizing filter provides is the ability to cut through reflections on non-metallic surfaces. Find a glass window with a good reflection of the surrounding objects in it and aim the camera with the polarizer at it. Look at the reflections through the camera and (after focusing) rotate the filter's front ring. You should be able to make quite a difference in how much reflection is seen in the glass.

Take the gear outside on a sunny day. With the sun directly on your right of left, look through the viewfinder at a horizon, engage AF, then turn the filter slowly around and observe the effect.

Try it also with the sun in front, behind, shoot more shots, compare, and then you'll have a feel for it!

Enjoy!