Do you love landscape photography? It provides ample rewards for those who are drawn to the outdoors. Chasing the light can be very exciting but it also poses some significant challenges. What you see versus what the camera sees can be two very different things.
What is High Dynamic Range and why it matters
Much of the best light comes with difficulties related to exposure, and all cameras have limitations when it comes to exposure. The problem is High Dynamic Range or HDR.
Your eyes have an immense dynamic range when it comes to scenes with extremes of bright and dark. Your eye adjusts so quickly you don’t notice it. But your cameras sensor, on the other hand, has a fixed dynamic range. If the scene you’re photographing exceeds that, the camera can’t capture all the details at both ends of the contrast range.
There are several methods for dealing with this limitation:
- You can underexpose the image and allow the darker elements to become silhouettes. But that only works in a few situations.
- You can use a graduated neutral density filter. This works best when there is a straight dividing line between the bright and dark areas of the image. Otherwise, the tops of foreground objects like trees become darker than the bottoms.
- Or you can use a method that works in all situations and the solution is simple. If the sensor can’t capture the full dynamic range in a single shot, take several shots at different exposures that span the dynamic range. Later, in the digital darkroom, blend the images together to make a single image.
There are two parts to the HDR process – capturing the image in the field and processing it in the digital darkroom. Let’s start in the field.
Setting up an HDR shot
Here are the things you need to do to set up an HDR shot for landscape photography. The starting point is your normal landscape configuration.
- It’s customary to use a tripod for landscape photography and this applies to HDR as well. However, with the exciting advances in alignment technology in applications like Photomatix Pro, more and more HDR photography can be done hand-held.
- Set your camera mode to Aperture Priority. You want all your exposures to maintain the same depth of field.
- Set your focus to manual (or use back button focus); you don’t want the focal point changing between shots.
- Use a remote release and set your drive to continuous mode. That way, you don’t inadvertently jiggle the camera when you press the shutter button. This way, one press of the remote‘s button takes all your shots.
- Set your exposure bracketing, you’ll typically want 2 stops difference between shots.
- Set the number of shots, typically 3. But be aware that in extreme conditions you may need 5 or more shots to capture the full dynamic range of the scene.
Note: Your camera may have restrictions on exposure bracketing and/or the number of shots, so you will need to work with that. The important thing is to get enough shots to cover the entire dynamic range.
Now you’re ready to go. For a more detailed introduction, see this article “Setting up Your Digital Camera for HDR Shooting”
How to know you need to do HDR
Your histogram will tell you if you need to use HDR. Here is an example of what you’re looking for.
The histogram spans the range of brightness from maximum dark on the left to maximum bright on the right. For each level of brightness, the graphs shows you how much of your scene has that tone.
The histogram above clearly shows a situation where HDR is needed. The histogram pushes up against the left side, which indicates the shadows are clipping and there is a loss of shadow detail. Similarly, the histogram pushes up against the right side where you have highlight clipping, again, with a loss of detail.
When checking your histogram for potential HDR problems, you only need to look at the left and right sides. What it looks like in the middle doesn’t matter.
For a full explanation of histograms, check out “How to Read and Use Histograms”.
Capturing the images in the field
You’ve identified a shot that requires HDR. Next, you’ve set up the shot and taken your set of bracketed exposures.
You got it. Or did you?
How do you know your shots spanned the entire dynamic range? If you’re thinking it’s the histogram, you’re right. You don’t need to check the histogram for every one of your shots, just two – the most underexposed (the darkest one) and the most overexposed (the lightest one).
The histogram on the left is the most underexposed shot. It is well away from the right side. In fact, there’s very little beyond the middle. You may think this is too underexposed, but experience shows that the best practice is to underexpose by too much rather than not enough. There can be areas that are extremely bright but too small to register. It’s better to play it safe.
The histogram on the right is the overexposed shot. Because it is pulled away from the left side, you can be confident you have captured detail in the shadows. Regardless of how many shots you took, these are the only two histograms you need to check.
Making the Best Use of HDR
In landscape photography, you have no control over the light. You need to work with what nature serves up. Sooner or later you will run into HDR situations.
With experience, you begin to anticipate when you need to use HDR. Here are some of those situations, with the before and after images displayed for each. The after image, by the way, is the result of the HDR blending and nothing else. More work will be done in Lightroom and Photoshop later.
Twilight
HDR conditions occur during twilight, the hour before sunrise and just after sunset. During most of this time, the dynamic range is well within your camera’s limits. But there is a period of about 10 minutes or so when the sky becomes very bright while the land is still dark.
This moment captured in Joshua Tree National Park, California, illustrates this issue.
The image on the left is the before image; a single exposure that captures detail in the foreground. Notice how the dramatic sky is lost. With HDR you get it all – foreground, sky, everything. And besides capturing the sky, look at the enhanced detail in the foreground.
Sunrise and sunset
Often during sunrise and sunset, you want to have the sun in the composition. The bright sun can create an extreme dynamic range, however, and can also confuse your camera’s light meter. The sky may get washed out or the foreground can be darker than you’d like.
Look at this photograph of Thor’s Hammer (above), captured at sunrise in Bryce Canyon National Park, Utah. The hoodoo to the right is an important part of the composition. Getting the starburst of the rising sun through the window adds to the interest.
But the before image without a sky misses another key element. With HDR, however, it all comes together and the moment is recreated.
Full moon at twilight
As it rises through the Venus Belt, a full moon makes an exciting image, with the band of color that sometimes appears in the eastern sky as the sun sets. The best time to capture this is one or two days before the actual full moon.
You may not think of this as an HDR shot. The dynamic range of the earth and the darkening sky is well within your camera’s capabilities. The moon, however, is in full sunlight. It is as bright as midday. So, the challenge is to capture the detail in the moon.
The before image has no detail in the moon or the shadows. But the HDR image captures the moon and can be worked with to produce a beautiful photograph. You might like to see how this turned out (below).
Dappled sunlight
In a woodland or forest on a sunny day, the sun’s rays pierce the canopy to create enchanting bright patches. It’s beautiful, but it presents a serious exposure problem. In the days of film with a limited dynamic range, you would likely pass it by.
This before image (above) has a problem that often goes overlooked; the foliage in the background is blown out. And not just that, but the fern at the bottom is also in the sun and it too is overexposed. But the HDR image handles both areas beautifully and, as a side benefit, produces richer colors.
This is just the beginning
There are a lot more situations where HDR can save the photograph. Slot canyons come to mind or rays of light in a redwood forest, as you saw above. The trick to avoiding HDR problems is to always check your histogram.
Another good practice is to do brackets shots even when it’s not obvious that the scene requires it. It’s good insurance. If you don’t need the bracketed images, you lose nothing. But if you need them and don’t have them you lose the photograph.
Processing in the digital darkroom
There are many tools that can blend your bracketed files. Even Lightroom and Photoshop now have very rudimentary HDR options, albeit without any significant controls. You get what you get.
The premier HDR tool is HDRsoft’s Photomatix Pro. HDRsoft has been around since the dawn of HDR photo editing. All they have ever done is HDR processing, and they are very good at it. Photomatix Pro provides a robust and powerful set of adjustments that enable you to create photographs ranging from natural to surreal, and even black and white.
Suppose you were photographing in Zion National Park, Utah at sunrise, and you took these three shots bracketed by 2-stops.
None of these photographs are very good on their own. The middle image, the underexposed one, captures the blue of the sky that isn’t in any of the other images. And the image on the right captures all the detail in the foreground. However, this is exactly what you want for HDR.
Let’s pick up the workflow where you have already uploaded your images into Lightroom and selected the files you want to process.
1. Initial Lightroom processing
Don’t do anything to your files before you do the HDR blending other than capture sharpening. In the Develop module, make sure all your settings in the Basic, Tone Curve and HSL groups are set to zero.
2. Export the files to Photomatix Pro
When you install Photomatix Pro with the Lightroom extension, an Export preset is created automatically. With all the files selected, in Library mode, click the Export… button in the lower left-hand corner. In the Export dialog, select the Photomatix Pro preset and click Export.
3. Make setting selections in the Export dialog
There are a number of settings in the export dialog box. The two most frequently used are Align images and Automatically re-import into Lightroom Library.
- Align images – Always click the Align source images checkbox. In the Preset pull-down menu select whether you captured the images on a tripod or hand-held. It’s a good idea to also click Crop aligned images.
- Automatically re-import into Lightroom library – Check this box because you will want to continue your workflow in Lightroom once you have your HDR image. In Output Format: be sure to select TIFF 16-bit. Also, click Stack with selected photo.
- Other Settings – You can explore the other settings for further control. The Show dialog with options to remove ghosts setting is like magic if any elements in your composition moved between exposures. It’s called ghosting. You have a tremendous amount of control in removing ghosting with this option. Check it out. Sooner or later you’re going to need it.
- When everything is set the way you want, click Export.
Lightroom converts the selected files to TIFFs, launches Photomatix Pro and exports the files. Photomatix Pro will do the initial processing and display the blended image.
4. Refine the image in Photomatix Pro
The image is already looking so much better. But you can do more.
The best place to start is the presets. Try out the various presets. There are over 40 of them, not counting any that you might have created. Everything from natural to surreal is covered. Detailed seems to work best for this photograph.
Check the histogram. Check the luminance, red, green, and blue histograms. The point of using Photomatix Pro is to eliminate clipping, especially highlight clipping and the histogram tells you how you’re doing.
Here, luminance has a small amount of highlight clipping. Red is fine but green and blue have a lot of clipping. That can be fixed with the White Point adjustment in the HDR settings group (you need to scroll down to see it).
White Clip – Set this to 0 and check your histograms again. The luminance and green clipping is totally gone but there’s still blue clipping. That’s not really a problem, though, because most of the blue has no detail.
Other HDR SETTINGS
Try the other adjustments in the HDR SETTINGS group. At the bottom of the panel is an explanation of what each does, so refer to that. After a little experimenting, setting Strength to 65 and Tone Compression to -4.0 produces a very favorable result with this image.
COLOR SETTINGS
Color Settings are fairly new and a great addition. Bumping both Saturation and Temperature to 4.0 is very pleasing.
It would be nice to draw more attention to the trees in their autumn colors. To do that, select Yellow from the Image Colors drop down and adjust the Brightness slider to 5.0, Saturation to 2.0 and Hue to -2.0.
5. The Results
Here’s how the image looks now. Looking good.
6. Finishing up
Click Next: Finish to continue. Photomatix Pro applies all of the adjustments you’ve made and gives you the option of a few more – Contrast, Sharpen, Crop, and Straighten. These are handy when you’re using Photomatix Pro to create the final image. But if you intend to do more processing in Lightroom or Photoshop, you might want to do your tweaks there instead.
7. Save and Reimport
Click Save & Reimport. Photomatix Pro will create a TIFF file and save it to the same drive as the original files. It will also add the new file to the Lightroom catalog so you can continue editing it there.
8. Finish your workflow
Continue your normal workflow with the file that’s just been imported. You could end up with something like this.
Final thoughts
Sometimes I’m asked if my photographs are what the camera saw. My response is, “No, because the camera doesn’t know what I’m feeling.”
Landscape photography can be so much more than just documenting experiences. It has the power to convey the emotions and states of mind that come upon us when we stand in the presence of such majestic scenery as this.
But there are times when nature challenges us. And with techniques like HDR and powerful tools like Photomatix Pro, our creative expression is unleashed, and we are able to make photographs that go beyond simply capturing the moment but hold a deeper meaning.
Do you have any questions about using HDR in landscape photography? If you do, please let me know in the comment area below and I will be happy to answer them.
Disclaimer: HDRsoft is a paid partner of dPS
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