In the following series of photos, I show how two filters can be used together to expand the dyamic range of your camera, and correct for contrasty light.
Each frame was taken on a tripod within seconds of each other. Every exposure was identical with the camera settings at: 1/5, f11, ISO 100, Cloudy WB, manual exposure, and autofocus.
In the first image, I metered the foliage in the foreground and set the exposure that provided detail in the foliage. As you can see, this worked well for the bottom part of the frame, but the sky was then overexposed.
PHOTO 1: NO FILTERS
For the second frame, I added a Hoya circular polarizer and twisted the filter until I saw an added vibrancy to the greens, and greater contrast in the water. Notice how much warmer the entire scene becomes, and the way the filter changes the appearance of the water.
PHOTO 2: CIRCULAR POLARIZER ADDED
In photo 3, I add a 2 stop graduated neutral density filter on top of the polarizer which as you can see below, changes a washed out white sky to it's natural blue appearance.
PHOTO 3: Two stop Neutral Density filter added
When I got home I applied some cropping, added a touch of saturation, and the final image is seen here.
This series was taken for Instructional purposes, and I hope you've found it helpful. Please feel free to share via Facebook, Twitter, etc.