The War on HDR

The discussion on a couple of photography blogs made me realize just how out of touch I am with the rest of the world regarding my opinion of High Dynamic Range photography.  There are even those who deny that HDR is photography, but we’ll touch on that later.  It started, innocently enough, with a Scott Kelby post titled “What They’re Not Telling You About HDR Images.”  I should have known something was up right off the bat.  He didn’t say “photographs” in the subject line.  He said “images.”  In the post, he discussed how non-photographers generally love these images while many photographers scorn HDR.  The same day, there was a post on Black Star Riding “Is HDR Imaging Ethical for Photojournalists?” That “image” word creeps in again, but at least they referenced photojournalists.  The article states that most news outlets have a code of ethics forbidding manipulation of the content of their images, and many prohibit HDR.

Why?  HDR combines multiple photographs into a single image to create greater detail in highlights and shadows.  The intent is to make-up for the lack of dynamic range of cameras compared to the range that the human eye can process. Some of these news outlets are re-thinking this policy and trying to determine if it’s acceptable to use HDR photos for news.  I don’t have an opinion as to whether a news outlet should or should not use HDR, but I do not see the process as unethical.  The point of HDR is not to deceive.

Joe McNally gave a talk at Photoshop World where he discussed the requirements given to him by National Geographic magazine.  Basically, he hands them the card with the images straight out of the camera.  He does not do any post-processing at all.  Sounds ethical, right?  There’s no manipulation, just the image as shot in-camera.  Everything done in-camera is precious.  When he went to Spain for an assignment to shoot full-size replicas of Neanderthals that used to roam in that area, he came across a woman and came up with an idea.  It was a double-exposure blending the woman who lives there now with a shot of the Neanderthal replica. Joe notes on his blog that this met the ethical standards of National Geographic. They didn’t run this shot, but they will run a double-exposure and insert a note to inform the reader.   I would hardly say that wasn’t a manipulated image.  Why is it OK to blend images in a double-exposure with two different subjects, but it’s not OK to blend images of the same subject in an HDR shot?  I’m confused.

The next day, Scott Kelby followed-up with a question about “over the top” HDR shots.  What makes an HDR shot over the top?  Is it the tonal range, the dynamic range, or something else?  Thus, the discussion in the comments of these posts continue the conversation, but do not truly answer the question for everyone.  That’s partly because some people have closed their minds to the possibility of including HDR as a photograph, much less whether it is acceptable, ethical, or desirable.  One man went so far as to claim, “There’s no such thing as a good HDR image.”  I had to ask him to define a good image, as my ignorance has allowed me to enjoy many HDR photos (or is it images?).

The process of creating an HDR image is tonemapping, and there are two types – global and local.  The process maps one set of colors to another to approximate a higher dynamic range on a medium that has limited dynamic range.  Cameras and computer monitors have limited dynamic range compared to the human eye. Global tonemapping applies the same process to every pixel in the image.  Local tonemapping treats pixels individually. The by-product of local pixel mapping are artifacts in the HDR image, commonly seen as noise and halo or ringing effects. Sometimes this appears unrealistic, even though the intent (increasing dynamic range) occurs.

If you stop at tonemapping, you may very likely arrive with a cartoonish image that may not look “real” to the viewer.  After all, we don’t commonly see noise or halos with our eyes. In order to complete the image, the development process may require some merging or blending parts of the original images.  This is where things start to fall apart for some people.

If you stop with tonemapping, you have a noisy, cartoonish image that some arrogant “photographers” reject as unworthy.  The code of ethics for news outlets prohibit manipulation, which could forbid blending portions of the original images into the tonemapped version.  Essentially, HDR fails to work for people who constrain themselves with these limitations.  I fail to see the ethical dilemma when blending images that are all of the same subject, but merely taken with different exposures.  It isn’t adding or subtracting from the subject itself, but rather from the luminance of the subject.

Of course, the artistic photographer without such constraints has a grand opportunity.  Not only is it possible to control dynamic range and luminance in greater detail than provided by a single exposure in a digital camera, but all of the other photo-finishing tools are still at the artist’s disposal. Just because you’ve blended the luminance of an HDR image doesn’t mean you’re done developing it.  Rather, it merely places you at the same place as if you had loaded an image straight out of the camera.  You can still apply Levels or Curves adjustments.  You can still use your filters and techniques to process the image as any other.  The only difference is the developer’s control of luminance.

Still, there are those who claim this is unnatural.  These are the same people who:

• Brag about the bokeh of their images
• Use time exposure to capture a stream of lights, star trails, or soften waterfalls
• Convert images to Black & White
• Desaturate images
• Oversaturate images
• Use artificial light
• Use graduated filters to control luminance
• Use lens flare
• Employ high contrast

Photographers have been creating unnatural images since photography began.  Trust me when I tell you that I’ve never encountered a person or landscape that was truly in monochrome.  I’ve never seen a waterfall look like cotton candy. These are the same people who speak reverently of Ansel Adams without considering that he blended images in his Zone System.  Ansel realized that any scene was composed of different exposure levels, and that a final result was often a combination of varying levels of luminance.  Yet, these same photographers expect us to do all of that in a single click.  It doesn’t work that way and it never has.

The final result is what matters, not the technique.  HDR is no more or less valuable than other photographic techniques. Since non-photographers aren’t involved in all of these decisions, they make their judgments on whether they like the result.  As Scott noted in his post (and I’ve also heard the same from Scott Bourne and David duChemin), they like HDR images. They don’t care how we got them.  That’s really all that matters, and why I have a hard time taking the HDR-haters very seriously.