There are few techniques in the photography world that divide our community as much as HDR. High dynamic range images, or HDR images, are a special type of composite image that combines several images at different exposure settings in order to create an image with increased dynamic range. The look provided by HDR is loved by many, and disliked by perhaps just as many. In today's article, we're going to take a better look at what HDR is, and get some opinions from photographers using HDR.
What is HDR?
As mentioned above, HDR images accommodate great amounts of exposure. A common goal of HDR is to increase the amount of areas that are visible in a photograph, bypassing the limitations of highlights and shadows.
Let's consider an average shot. In a typical photo, there are very bright areas (called highlights) and less lit areas (referred to as shadows). Cameras are limited in the amount of data that they capture. The space of shadows to highlights that a camera can capture is called its dynamic range. Again, although technology is improving and each generation of camera improves upon the amount that can be captured, standard image sensors are limited in the amount of dynamic range that they can capture.
HDR imagery seeks to increase this limited dynamic range by combining exposures. The limits to dynamic range only apply to each individual photo, and through HDR, we can blend photos and increase the dynamic range in the resulting composite image by using editing.
Although there are some "single shot HDR" techniques, true HDR imagery requires several exposures. We use a technique called "bracketing" to vary our exposure settings and properly capture the set of images. When we bracket our shots, the camera fires a succession of images with slightly altered settings to capture photos of slightly varying exposures.
By the time we've snapped this range of photos, there are major differences between them. Below is an example of a set of five bracketed images, which is a good number for most HDR purposes.
When you bracket, you set your camera to various "steps" apart in exposure. For the above images, each photo represents one stop in either direction. The image in the center is a standard frame, metered in evaluative mode and captured in aperture priority mode. The images to the left are underexposed (darker than suggested) and the images to the right are overexposed (brighter than suggested). Each image is bracketed by a full stop in either direction, so that the image at far left is two stops underexposed, and the images at far right are two stops overexposed.
Let's analyze some of the images. In the center frame, notice how the sky appears. It's certainly not a deep blue as we might imagine a sky. Again, this is because our camera is limited in the amount of dynamic range (range between shadow and highlight areas) that it can capture. However, notice in the two stops underexposed photo, the sky is blue as we might want it to appear.
Now, consider the shadowed areas near the rock. In these images, the +2 "overexposed" exposure brings the rocks out of the shadowed region and shows enough light on them to illustrate the detail.
If you've followed along, you might be beginning to understand the benefits that combining shots in the HDR style can provide. By compositing the above images, we can show the range of highlights to shadows properly. Below is an HDR blend of the images, composited in Adobe Photoshop.
Now that we have an understanding of the HDR technique, let's get the impressions of some HDR photographers. For this article, I contacted two photographers who use HDR in their work in different ways to get their thoughts on the high dynamic range technique, and why they think it can be both loved and hated
A big part of the differences in the "HDR look" is dependent upon the software that is used to create the HDR composite. Some applications tend to give the images a cartoon type effect, while others (like Photoshop's built in HDR function) tend to stay more true to the original look of the source images. Every application has some settings that have an effect on the output image. Common HDR software used by photographers includes Photoshop, Photomatix, and HDR Efex Pro. Each of these provides different options for how the final image will appear.
In doing research on this article, I decided to contact a couple of photographers that use HDR. I tried to survey photographers who use HDR in different ways to achieve different results.
The first person I contacted was Simon Plant, a fellow writer here at PhotoTuts+. Simon was one of the first photographers to jump into using HDR, and he has used it extensively in his commercial work to set it apart and give his images a unique look. Here's out he feels about it now.
"The word HDR reminds me a bit of the word "Cokin" in the late 80's early 90's. You may or not remember, but Cokin made a whole array of filters which often could be found free on the front of monthly magazines here in the UK. There was nothing wrong with them but EVERYONE used them so you'd get landscapes with tobacco-colored skies, rainbows and of course the famous starburst filter. Very tacky and mostly uncreative, but even I indulged!"
Plant also said that he uses the HDR technique "as another problem solving tool to overcome the contrast restrictions often inherent in shooting certain subjects like interiors." He added the example that "if I was shooting an interior, but wanted to show details in the windows showing the exterior. I'd look not to darken the windows too much as this would just look too false."
In this image by Simon Plant, the HDR technique was tastefully applied to create a great final image. The technique was used to keep the exposure proper in both the sky and on the surface of the sand as well. Multiple exposures were taken at varying settings to capture the range of exposures.
I also spoke with Italian photographer Giuseppe Sapori. He too is a user of HDR imagery, and his photos may be something closer to what you envision when you hear the term "HDR." His use of the technique differs from Simon's. Sapori uses the technique to paint the scene in a way that most people would not see it.
Sapori says, "Some people say that HDR is nothing but an effect, a fashion, a post production work aimed at making regular images extremely perfect, almost unreal and "fake". Actually, I rather think that dealing with HDR means dealing with photography in all respects. An HDR image, composed of multiple exposures and tone mappings turns out definitely improved, better contrasted and more vivid in colors.
"Processing a HDR photo does not mean to create a beauty that doesn't exist, but recognizing the best of the beauty in photography. Improving our shots pointing toward the enhancement of details and colors is part of this style of photography that travels on a thin line between real and surreal. I've always liked HDR photography since I grabbed a camera for the first time, I get real gratification from it and of course a lot of fun."
Italian HDR photographer Giuseppe Sapori uses the technique differently, to convey a scene in an unconventional way.
These two photographers both use HDR, but in completely different ways. As photographers, our aims differ from one person to the next. HDR is a technique that can accomplish a variety of objectives as photographers, depending on how it is used.
The Author's Take
Personally, I feel that although the highly processed, surreal style HDR is not my favorite photo effect. It certainly has its place as its legitimate technique in a photographer's bag of tricks. As a wedding and portrait photographer, you probably won't find any high dynamic range photos in my portfolio, but the ability of other photographers to harness HDR to their liking is something I envy.
I also feel that part of the reason that many photographers resent HDR is the public's general response to it. I have noticed that many people who don't consider themselves interested in art will immediately gravitate toward HDR images and complement their look. I believe that many serious, non-HDR photographers resent this response, and thus do not typically favor HDR.
HDR is one of many techniques that photographers use in order to achieve a unique look. Although both loved and hated, I think that most photographers would agree that it has legitimate uses and can create effects that are otherwise unattainable with single exposures.
What do you think of HDR? Do you love it, hate it, or are you somewhere in between? Be sure and leave a comment to let us know what you think.