lovelifey: [Photography] HDR Photography: A Step-By-Step Guide

The post HDR Photography: A Step-By-Step Guide appeared first on Digital Photography School. It was authored by Barry J Brady.

a guide to HDR photography (step by step)

What is HDR photography? And how can you use HDR techniques to create one-of-a-kind, breathtaking photos?

In this article, I explain everything you need to know about high dynamic range imaging, including:

An easy-to-understand explanation of HDR shooting
When you should use HDR techniques (and when you should avoid them)
Step-by-step instructions for taking HDR photos in the field

So if you’re ready to create incredible high dynamic range photos, then let’s dive right in!

What is HDR photography?

HDR photography is a technique where multiple bracketed images are blended together to create a single beautifully exposed photo.

In other words, you take several photos with different exposures, then you combine them – in a program like Lightroom or Photoshop – to create a highly detailed file.

Why is this necessary?

Your camera can only capture a limited range of lights and darks (i.e., a limited dynamic range). If you point your camera at a dark mountain in front of a bright sunset, no matter how much you tweak the image exposure, your camera will generally fail to capture detail in the mountain and the sky; you’ll either capture an image with a beautiful sky but a dark, detailless mountain, or you’ll capture an image with a detailed mountain but a bright, blown-out sky.

High dynamic range photography aims to address this issue. Instead of relying on the camera’s limited dynamic range capabilities, you can take multiple photos that cover the entire tonal range of the scene.

Then you can combine the detailed sections of each photo and finish with a file full of well-exposed shadows, midtones, and highlights.

In the case of the mountain at sunset, you could take three images:

A darker image to capture detail in the sky
A brighter image to capture detail in the mountain
A “standard” image to capture detail in the midtones

Then you could blend the three files, using the sky from dark image, the mountain from the bright image, and the midtones from the middle image. Make sense?

When should you use (or avoid) HDR photography?

Most scenes don’t require HDR techniques. Cameras have limited dynamic range capabilities, sure, but they’re still capable of handling most standard situations; in other words, you don’t need to do high dynamic range photography all the time.

And HDR techniques come with significant limitations. To use the HDR process, you need to take at least two “starter” images, and neither the scene nor the camera can shift from shot to shot. You should always use a tripod, and you should aim to capture stationary scenes with little-to-no movement.

Therefore, I don’t recommend HDR photography when shooting action, such as sports, wildlife, birds, or even portraits; your subjects will move frequently, and you’ll struggle to get two bracketed images.

On the other hand, HDR techniques are great for landscape photography, real estate photography, architectural photography, and cityscape photography. These genres allow for slow, tripod-based shooting, and the scenes feature limited movement, too.

More specifically, you should use HDR photography when you encounter stationary scenes with very light and very dark tones. Here are a few common scenarios where HDR techniques can be a big help:

Sunrise and sunset landscape and cityscape scenes (with a bright sky and a dark foreground)
Real-estate and architectural interior scenes (with bright windows and/or artificial lighting)
Twilight and night scenes (with artificial lighting and deep shadows)
Landscape scenes with a mix of bright light and shade

Of course, it’s impossible to say for sure whether a scene will benefit from an HDR treatment, and camera sensors are steadily getting better at handling high dynamic range scenes. But when in doubt, you can always shoot a few bracketed exposures; that way, when you arrive home, you can decide whether you captured enough detail in one of your shots or whether you need to blend the files together.

How to do HDR photography: step by step

In this section, I offer clear, step-by-step instructions for creating an HDR image, including both file capture and processing.

Step 1: Set up your camera

As I emphasized above, it’s important to use a tripod when shooting HDR, so if you’re planning to use HDR techniques, make sure you keep a tripod handy.

Once you find a scene that could benefit from a high dynamic range treatment, mount your camera on your tripod and determine your composition (the way you would when capturing a normal, non-HDR shot).

Then select your camera settings. First, adjust your camera mode to Manual; you don’t want the exposure changing from shot to shot.

Set your ISO at its lowest value to prevent noise, and choose an aperture that gets you your desired depth of field (I often shoot at f/8 to f/11, but you can go wider or narrower depending on your goals). Choose a shutter speed that gives you a balanced exposure (that is, make sure you expose for the midtones, not the highlights or the shadows). Here, it can help to look at your camera’s exposure bar, which is generally visible at the bottom of the viewfinder.

Switch your lens over to manual focus – you don’t want the point of focus changing between shots! – and adjust the focus ring until you get the result that you’re after.

Step 2: Take a “correctly” exposed image

Once you’ve set up your shot, take one last look at your camera settings.

If your shutter speed is below 1/60s or so, make sure you use your camera’s two-second timer or a remote release to prevent camera shake.

Finally, take your first shot. Review the results on the back of your LCD. The midtones should be well exposed, while the highlights and shadows are much less important.

If your image is very dark or very bright (i.e., exposed for the highlights or the shadows, respectively), I’d recommend adjusting your shutter speed and reshooting. Then move on to the next step:

Step 3: Take an overexposed and an underexposed image

Keep your ISO, aperture, and point of focus consistent. Then lower your shutter speed by a stop or two and take a photo.

The result should look overexposed – but the darker portions of the scene should feature plenty of detail. (You can check this on your LCD or your camera’s histogram.)

Next, raise your shutter speed several stops, then take a photo. This time, you should get an underexposed image, one that is missing lots of shadow detail, but that accurately exposes the brightest parts of the scene.

Step 4: Consider the results (and take more photos if necessary)

At this point, you should have three photos: a standard (midtone) image, an overexposed image, and an underexposed image.

In many cases, this will be enough for a nice HDR blend, but if your scene features an extremely high dynamic range, you may want to shoot five photos, seven photos, or even nine photos. Simply keep adjusting the shutter speed for increasingly lighter and darker photos until you’re satisfied with the results.

Over time, you’ll get a sense of the number of shots you need to create a good HDR file, but I always recommend you review your shots – and their corresponding histograms – on your LCD. If you find that you’ve captured sufficient detail, you can move on to the next step:

Step 5: Blend the files together

After an HDR shoot, you’ll need to blend the files together for a well-exposed composite image.

The specifics will depend on your choice of post-processing software, but most programs make it pretty easy to create good-looking HDRs. Here’s how to create an HDR blend in Lightroom:

First, import your photos.

Select all the files you need to blend together, then right-click and choose Photo>Photo Merge>HDR.

An HDR window will appear. I’d recommend checking the Auto Align box, especially if you shot handheld or your tripod moved from shot to shot. You can also check the Auto Settings box.

If your scene had moving elements (such as blowing branches or people walking), select the Medium or High deghosting option.

Finally, hit Merge, and wait while Lightroom processes your image!

Step 6: Process your HDR file

At this point, you should have a high dynamic range file – but what should you do with it?

I’d recommend some standard post-processing. Tweak the exposure, the shadows, and the highlights; add (or subtract) contrast; add saturation and play around with color grading; sharpen the shot as required; then export as a JPEG for viewing.