Techniques

High Dynamic Range Options

by Tim Grey | May 31, 2012

© Tim GreyEvery now and then it seems that a particular issue in photography becomes especially popular, and I start to get a relatively large number of queries on that topic to be addressed in my daily Ask Tim Grey eNewsletter. Recently, the subject of high dynamic range (HDR) imaging became the focus of several questions from readers. One reader addressed the more philosophical issues at play with HDR, including in a question the following thoughts:

I find photos made by the HDR method a bit dull, while those with added presets or adjusted a bit cartoonish and surreal. On the other hand, following a method of underexposing a photo and then post edit it I found to get better results to my liking.

There isn’t, of course, a simple answer that addresses all possible scenarios or the preferences of all photographers, as I indicated in the opening line of my answer to the query:

The underlying issue here is how to deal with a scene that exhibits high contrast, and of course there are several possible ways to approach such a scene.

At a very basic level, the options when dealing with a scene exhibiting a higher dynamic range than your camera is capable of recording in a single capture are to simply create a single exposure and accept the fact that some detail will be lost in the highlights or shadows (or both), to capture two images (one for the highlights and one for the shadows) and then blend them together later, or to capture a series of images with
different exposure values and then blend them using HDR software to compress the full dynamic range of the scene into a single image.

The best solution for a given situation depends both on the nature of the scene you’re photographing as well as your own preferences as a photographer. As I explained in my answer to the original question:

I use all three of these methods under different circumstances. I agree that HDR images can often look a bit “flat” since the tonal range is being compressed, and can look a bit cartoonish when pushed too far in post-processing. But sometimes I like the look you get with HDR processing, so I do use it from time to time.

In other cases I’m simply trying to achieve something that looks more realistic for a scene that exhibits a high dynamic range, and in those cases I’ll often blend two exposures together. And sometimes I just accept the limitations of my camera and capture a single exposure, even though detail will be lost in the shadows or highlights (depending on my exposure).

One of the things I see all to often, however, is a photographer who dismisses a possible solution based on their own bias. I’m not suggesting that every photographer should learn to create HDR images and start looking for opportunities to create them. I myself only create HDR images periodically. Rather, I’m suggesting that sometimes it is a very good thing to get outside your comfort level as a photographer, and to learn new techniques. Doing so will help expand your knowledge as a photographer, and just might lead to some great new images that you would have otherwise missed.

Horse at sunrise © Tim Grey

I shared similar sentiments regarding the various options when photographing a high dynamic range scene in part of my answer:

I encourage you to try all three of these methods to get a better sense of what’s possible. But I also encourage you to listen to your instinct as a photographer. If you’re generally not pleased with the results of an HDR capture, don’t take that approach just because it has become a popular solution. I believe you’ll be happiest with the final photo if you feel good about the approach you’re taking. First and foremost you should focus on creating a photograph that you’re happy with. If others enjoy it as well, that’s a bonus.

This discussion led to some follow-up questions, including a question from one reader asking if it might make good sense to simply capture a single exposure in RAW, and then process multiple copies of that same RAW capture to create the exposure variations that could be blended into a single HDR result. There’s no question this is possible, but the results often won’t be optimal, as I address in my answer:

There’s no question that a RAW capture includes enough exposure latitude that you can achieve a good effect with this type of technique. For situations where the dynamic range of the scene is not extremely wide, the technique will work reasonably well. For other situations with an extreme dynamic range, the technique will work reasonably well, but not as good as can be achieved with multiple captures separated by one stop (or less) in exposure.

Your approach using Lightroom is effectively the same as processing multiple versions of a RAW capture using other software (such as Adobe Camera Raw). You can most certainly achieve a good result with this process, but frankly you can also achieve a similar effect by applying targeted adjustments throughout the image.

The results you achieve won’t be as good in terms of detail and noise levels compared to a “true” HDR approach, but in many cases the results will still be good. So, if you neglected to capture multiple exposures, you can certainly apply targeted adjustments or blend different versions of the image. But if the scene represents a high dynamic range you are better off capturing those multiple exposures from the start.

Melk Abbey © Tim Grey

As photographers we face a wide variety of challenges, and of course in most cases there are more than a few possible answers to those challenges. High dynamic range imaging is just one example, but one we are likely to face somewhat frequently. Regardless of the challenge you might face in a particular photograph, I think the best thing you can do is consider all of the possible solutions, and then determine which one
(or more) solution might be the best fit for the subject, the intent of the photograph, and your own tastes as a photographer.

To get free daily answers to questions related to digital photography and imaging, sign up for the Ask Tim Grey eNewsletter at www.asktimgrey.com.

About the Author

Tim Grey is an educator in digital photography and imaging, offering clear guidance on complex subjects through his writing and speaking.

Tim has written more than a dozen books on digital imaging for photographers, has published dozens of video training courses, has had hundreds of articles published in magazines such as Digital Photo Pro and Outdoor Photographer, among others. For more than a dozen years he has been publishing the daily Ask Tim Grey eNewsletter, answering questions from photographers, and produces the related Ask Tim Grey Podcast. He also publishes the monthly Pixology electronic magazine, and publishes video training courses through GreyLearning.com. Tim teaches through workshops, seminars, and appearances at major events around the country and around the world.

Tim can be reached via email at tim@timgrey.com.

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