The polarizing filter is one of the least discussed tools every photographer should learn to use properly. Many of the new photographers I have in my workshops have never heard of this wonderful gadget. They often know polarized sunglasses can be used to see fish in a stream, but never thought about having that option with their camera.
In very simple terms, polarization takes away glare and reflections on shiny surfaces such as water and glass (but not metal). Reflections on water could be a lake-full of water or a droplet of water… or even water vapor. A hazy sky may be caused by humidity, by eliminating the reflection off the vapor will allow the blue sky to be more saturated. Autumn leaves can have their colors “pop” and detail on moist moss or wet rocks will be seen.
How does it work? Light travels in both horizontal and vertical wavelengths. A polarizing filter eliminates one of these waves, thereby eliminating the reflection. The filter itself can rotate while on your camera’s lens, therefore you can adjust the amount of polarization you use in each image. Just a 1/4 turn in either direction will change the image from no polarization to 100% polarized. However, the angle you are to the path of the sun can also make a big difference. If you are parallel to the sun’s path, the filter will have almost no noticeable effect, while 90 degrees to the sun’s path with offer the greatest effect.
So why don’t we use a polarizer all the time? Using a single lens reflex (SLR) camera allows you to easily see the amount of polarization affecting the image as you turn the filter. Sometimes you don’t want to eliminate or even reduce the reflection like the waterfall photo at the top of this post. In this case, the golden color of the autumn beech tree leaves created a wonderful “River of Gold” effect… polarizing would have eliminated the reflection (see samples below). So look at these samples (place your curser on the sample images to see which were polarized and which were not if you’re not sure.
Next photo lesson I’ll talk about how I made these waterfall images… all of which were taken during some of the Waterfall Photography Workshops I teach in spring and fall. Check out our upcoming workshops!