To HDR or not to HDR

Sometimes capturing a scene that has very bright and very dark areas with a camera can be impossible, because both film and the digital sensor can resolve fewer stops of light than the human eye. Traditionally, this limitation was overcome by using a graduated neutral density filter, which darkened the bright portions of the scene to allow the film to expose the entire scene correctly. With the advent of digital technology, there has been a trend to move instead to post processing and digital manipulation to achieve similar results.

HDR (or High Dynamic Range for the uninitiated) has been sweeping the digital photography world for the past couple of years, mostly thanks to some new software that makes creating these images easy. The goal is simple: use several shots of the same scene at varying exposures to create a single image with a greater dynamic range (the range between pure white and pure black) than your camera can capture. Unfortunately, this goal is usually not achieved with results that look correct to the human eye. The final images appear flat and with low contrast, and the colors tend look almost cartoonish. This can be overcome to some degree by increasing the black level and overall contrast – however correcting the color issue is difficult.

The solution is to go back to digital basics. Instead of letting software automatically combine 3 or more shots at different exposures, combine 2 or more images yourself in an application such as Adobe Photoshop using stacked layers and various blending techniques. Photographer Glenn Randall covers some of these techniques and the principals behind them in his recent article for Outdoor Photographer magazine. The images below demonstrate using image blending verses an HDR software approach.

High Dynamic Range photo of Zion National Park
High Dynamic Range photo of Zion National Park, combining three images shot at different exposures

The above image was created by blending three photographs of different exposures together using software. Once this was done, the contrast was increased significantly. However, as you can see, the colors still look unnatural, with too much yellow in the rock. In addition the two rock faces in the background are washed out.

The image below combines two the the images used to create the previous image. The foreground and mountain were exposed with no evaluative metering compensation. The sky was exposed in a second shot at -1 stop, and blended into the foreground using a graduated mask. The result is more natural looking.

Dramatic cliffs rise above a snowy riverbed with foreground trees, Zion National Park
Two images of Zion National Park blended together using a gradient mask

Some people like the aesthetic of HDR images, and that is great. It brings a new artistic flair to the world of digital photography. But since I am usually trying to create a final photograph that accurately portrays what I see in nature, using the blended approach often works better for me.

It pays to be prepared

A river otter clings to a log, submerged in an algae-filled pond
A river otter clings to a log, submerged in an algae-filled pond

“Chance favors the prepared mind,” goes the saying by Louis Pasteur. I wholeheartedly believe this is true – in fact, I would say that it is very uncommon to be lucky without being prepared. The image above demonstrates this belief.

Kerry and I were up in Mt. St. Helen’s National Volcanic Monument taking photos of the mountain and just being tourists. We were blessed with great weather and clear skies, so we decided to take a short hike out into the ash flow that wiped out the Toutle River in the 1980 eruption. I was primarily interested in gaining a new vantage point on the mountain for landscape shots, but as almost an afterthought, I decided to take a second camera body with a telephoto zoom, just in case we saw any wildlife.

Now, I almost never take a lens this big with me on a hike unless I’m going for the express purpose of setting up somewhere for a particular animal. The lens and body together was pushing over 4 lbs, so it’s not the most comfortable thing to sling over your shoulder. But the hike was only 2.5 miles, so I figured, “why not?”

About half way through the hike, we came to a medium sized pool of water, filled with bright green algae and surrounded by thick vegetation. Just as we were passing the water, two river otters burst out of the bushes and jumped into the pond. At first they watched us intently, to see what we were all about. Soon, however, they relaxed and began playing and eating clumps of algae. “Luckily” I had my second camera with the long lens ready to go, and preset to the correct settings for wildlife photography. Because of this preparation, I didn’t miss any of the action while I fiddled with controls. If I had not considered the “what if” possibility of seeing wildlife, and just stuck with my wide angle lens, I would have missed these otters completely.

So next time you’re headed out, think about all of the different situations you might run into. It might lead to bringing different gear, or just pre-visualizing a potential photograph you might be able to create. I am grateful for that extra moment that I paused to think – in this case, it certainly helped me get “lucky”.

Watch your speed!

Policeman uses a radar gun to catch speeders crossing the Golden Gate Bridge
Policeman uses a radar gun to catch speeders crossing the Golden Gate Bridge

I took this photo last month when my wife Kerry and I were heading up the coast north of San Francisco. The officer casually walked up to the wall and whipped out his radar gun (or perhaps it was laser). It wasn’t long before he was radioing the descriptions of cars to other CHP officers further up the highway. I was impressed at the distance the speed gun could cover.

So next time you’re headed out for the weekend, beware. You never know who’s watching you. Above all, drive safely!