It seems computers can do most anything with an image now a days. So why bother with all those cumbersome filters? The answer is that most of them are still superior to the techniques used with a computer. Plus, if the image is more accurate coming out of the camera, less time and effort will be needed in post processing. Lastly, understanding the play of light and filtration is an important cornerstone to understanding photography, which is simply put, capturing light.
This post will concentrate on the polarizing filter and more specifically, the circular polarizing filter. So what is a polarizing filter? DPS already has a great post on How to Use and Buy a Polarizing Filters which should be your first stop in understanding these filters. In a nut shell, a polarizing filter will reduce the reflected glare off of water, sky (particulate), metalic surfaces and anything else with a good reflective surface, even including leaves. It helps increase contrast and provide better, truer color when used properly. A circular polarizing filter is mounted on a ring allowing it to spin for variable effect. You may choose the amount of polarizing by simply turning the ring until the desired results are viewed.
With all that in mind, it may seem obvious that a computer can make the same changes. Bumping up contrast and adjusting color is as easy as a couple of mouse clicks nowadays. My goal in this post is to compare the two techniques and let you draw your own conclusion. Knowing that good polarizing filters cost more than $100, I hope you can be a little more informed if you wish to go that route.
Let’s get started with a couple of untouched yet cropped photos straight out of the camera.
First off, can you guess which one used a polarizing filter? It is the second image. More true greens, less glare and more detail on the distance bluffs are the giveaways. You may also notice the slight cloud gets a different treatment, changing from a gray line to more of a white. The top image was shot at ISO50 1/100 and f/5.6 while the the bottom image was slightly slower at 1/50 and f/5.6 due to the tinting of the polarizing filter. Canon 5D 28-300mm L lens @ 300mm. And a special thanks to Natalie for her post regarding camera shake to help keep them clear.
If the look of the bottom photograph is what’s desired, it’s time to play around with the first image. Here are the steps I took (read from bottom up):
I don’t claim to have mad Photoshop skilz and this is the as close as I got.
Attempting to remove the haze from the distant cliffs proved problematic. While a better effort could be made with some tools in Photoshop CS3, the time and expense was beyond the scope of this test. Increasing saturation or hue over what has attempted created undesirable results.
Now the questions are to you: Which rendition do you prefer? Do you use a polarizing filter often and if so, please offer up any tips you may have in the comments section below.
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