The post A Comprehensive Guide to Dynamic Range in Photography appeared first on Digital Photography School. It was authored by Simon Ringsmuth.
Dynamic range is a fundamental concept in photography, one that every photographer must understand. Unfortunately, it generates a lot of confusion, thanks to its technical components and difficult-sounding name.
But dynamic range isn’t nearly as complex as you might think. And in this article, I break it all down for you. I explain:
- What dynamic range in photography actually is
- How dynamic range affects your images
- How you can use your understanding of dynamic range to instantly improve your photos
By the time you’re done reading, you’ll be well equipped to capture photos that require major dynamic range know-how – in particular, landscape, cityscape, and night images.
Let’s get started.
What is dynamic range in photography?
Dynamic range refers to the range of tones in a scene, from the darkest, blackest shadows to the brightest, most brilliant highlights. The more tonal range present in a scene, the greater the dynamic range.
So a scene full of bland, gray midtones – such as an elephant against a tan wall – has a low dynamic range, while a scene with intense highlights and shadows – such as a sunset over a shadowy forest – has a high dynamic range.
In photography, dynamic range is quantified in terms of stops, where each stop corresponds to a doubling of light levels. The details are irrelevant; what’s important is that a scene with 10 stops of dynamic range has greater tonal variation than a scene with 5 stops of dynamic range, and so on.
But how does this affect your images?
Every camera is capable of capturing a certain dynamic range. And once the dynamic range of the scene exceeds the dynamic range capacity of your camera, then you get blown-out highlights and/or clipped shadows (i.e., loss of detail at the dynamic range extremes), which is a major photography no-no and should generally be avoided.
For example, a standard camera might offer a 12-stop dynamic range, which makes it very easy to capture an image like this one:
But if the sun were to come out and backlight the goose, the dynamic range would increase dramatically and your camera would struggle to record both the shadows and the highlights, as you can see here:
In the scene pictured above, the background fountain was so bright and the foreground shadows were so dark that my camera couldn’t handle the entire dynamic range. While I managed to retain most of the highlight detail in the areas behind the goose, the shadows were clipped, leading to black, detailless patches in the foreground. (And had I deliberately increased the exposure to brighten up the foreground, the reverse would have occurred: nice detail in the foreground but a loss of detail in the background highlights.)
What causes high versus low dynamic range?
Dynamic range is caused by a combination of your subject and the light.
Certain subjects are bright, such as silver cars, white egrets, and snowy landscapes. Other subjects are dark, such as black motorcycles, oak tree bark, and light-blocking curtains.
If you place a dark subject on a dark background or a light subject on a light background, you’ll have a low dynamic range scene (i.e., very limited tonal variation).
But if you place a dark subject on a light background, like a black motorcycle in front of a snow-covered hill, you’ll generally have a high dynamic range scene.
The light matters, too. High-contrast light, like you find at noon on a sunny day, creates lots of highlights and shadows, resulting in a high dynamic range scene. Whereas overcast light is very flat; the world under a blanket of clouds features far less tonal variation. (The same is true of shade, which is why portrait photographers often prefer to position their subjects under trees during midday photoshoots!)
Note that the subject and the light together create the dynamic range of a scene. If you put a dark subject in front of a light background then add high-contrast lighting, the scene will increase in dynamic range. And if you put a dark subject in front of a light background then add flat, low-contrast lighting, the scene will reduce in dynamic range.
So dynamic range cannot be evaluated in terms of only subjects or only light; both factors matter.
For instance, I shot this image with my subject in shadow while the background was lit by the sun, which resulted in a relatively high dynamic range photo:
But by adjusting the position of my subject, I was able to shoot against a shady background, which evened out the light for a low dynamic range image:
In other words, by adjusting the light, I was able to change the dynamic range, even though the true tonal value of the subject and the background didn’t change significantly.
Dealing with high dynamic range scenes: four simple strategies
High dynamic range scenes can cause problems for photographers; they make proper exposure very difficult, and beginners often get frustrated by the loss of detail in HDR shots.
So what do you do? How do you handle HDR subjects, such as a shadowy foreground against a beautiful sunset?
Below, I share four methods. Note that no single option is necessarily better than the others. It all depends on the situation!
1. Bracket your images
Bracketing is the process of taking several images at different exposure values in the hope that one image turns out well exposed. The simplest – and most common – method of bracketing involves taking three images, each with a slightly different shutter speed.
That way, when you get home after a photoshoot, you’re able to pick the image with the best exposure, then you discard the others.
Bracketing works well when capturing scenes with a relatively high dynamic range, as long as the DR isn’t so high that it exceeds the capabilities of your camera. For instance, if your camera can capture 12 stops of dynamic range and the scene you’re photographing sits at around 10, as long as you can get the exposure just right, you’ll be able to pull details out of both the highlights and the shadows. On the other hand, if you miss the exposure even by a couple of stops, you’ll lose detail and the shot will be ruined.
So by bracketing in such a scenario – that is, by shooting several variations, just to be safe – you can ensure you do get that perfect exposure and come away with a usable image. Here, your camera’s histogram and LCD playback function are also hugely helpful as you can check each file to ensure you’ve avoided clipping (then make any necessary adjustments to the exposure based on what you see).
Note that bracketing is a generally useful practice, one that will increase your exposure accuracy even when you’re photographing scenes of medium dynamic range, so feel free to bracket as often as time allows!
However, while bracketing is great for medium and medium-high DR scenes, it won’t give good results when the dynamic range is extremely high, such as when photographing intense sunsets or cityscapes at night. In such cases, even if you nail the exposure, you’ll still end up with lost details, so you’ll need to use another method:
2. Do HDR blending
HDR photography involves capturing several images with different exposures (i.e., bracketing your photos, as explained in the previous section), then blending the images together for a final, perfectly exposed file.
For instance, if I’m photographing inside a house, I might take one shot that captures the exterior details:
And a second shot that captures the interior details:
And blend them together for a final image that includes details in both areas:
This method of imaging is great for handling sunrise and sunset scenes as well as interior-exterior shots, but it does come with several drawbacks:
- You generally need to use a tripod to keep the framing consistent.
- You must spend extra time processing each image (though many exposure-blending programs are so good that the editing time increases by only a few seconds per shot).
The post-processing workflow can seem daunting at first, but programs such as Lightroom and Photoshop have easy, built-in algorithms for handling the HDR merge process (and if you require utmost control over the highlights and shadows, you can learn to do manual blending, a complex process that can nevertheless give you outstanding results).
3. Use a graduated neutral density filter
Prior to the development and popularization of HDR blending, landscape photographers used graduated neutral density filters, or GNDs, to handle high dynamic range scenes.
Such filters simply mount in front of the lens and feature a gradient that goes from clear to dark.
The idea is to position the darkest part of the filter over the brightest part of the scene (generally the sky) and the clear part of the filter over the darkest part of the scene (generally the foreground), thus reducing the overall dynamic range and allowing you to capture the entire scene in beautiful detail.
Some photographers still use GND filters, especially those who prefer to spend less time editing and more time shooting. But high-quality filters can be expensive, plus they offer less flexibility than HDR blending, so their popularity has waned.
My recommendation: Unless you love the idea of using GND filters (or you’re a film photographer), go with one of these other strategies instead.
4. Skip the shot (or wait for better light)
Oftentimes, high dynamic range scenes are predictable.
Certain types of light give rise to bright highlights and deep shadows, such as harsh midday lighting or backlit evening light.
Now, in such cases, you may want to capture the high dynamic range scene, and when that happens, you should use one of the strategies outlined above.
But in other cases, if you’re struggling to capture a well-exposed shot, one option is to just move on. Skip the shot. If you like the overall scene but aren’t attached to the current lighting, you can always come back later when the light is less contrasty.
This is particularly important when you’re shooting landscapes in the middle of the day. The harsh light will create powerful shadows and highlights, your camera will fail to expose for the entire scene, and even if you use HDR blending, the result probably won’t look very good simply because midday light and landscapes generally do not mix well.
Sure, there are some exceptions, but it’s often best to avoid midday landscape photography entirely. Instead, come back at sunrise or sunset, when the sky looks amazing and the scene is less contrasty. You might also consider coming back on a cloudy day, especially if you’re photographing in a forest.
Ultimately, the choice is up to you – but just remember that, in photography, patience often pays off.
Dynamic range and modern camera technology
As I’m sure you’ve gathered from reading the previous sections, dealing with high dynamic range scenes takes time. Each method of handling HDR situations involves extra shots or extra steps, which isn’t always convenient (and in certain cases, isn’t feasible).
Fortunately, as camera sensors have improved, dynamic range capabilities have soared. While photographers once needed several images to photograph an HDR scene, certain cameras – such as the latest full-frame DSLRs and mirrorless models – are capable of capturing 13-15 stops of tonal range. In other words, they can record an entire HDR scene in a single file.
For instance, this sunrise image appears to lack detail in the shadows, which you might expect from such a high dynamic range scene:
But as a bit of post-processing reveals, thanks to the impressive dynamic range capabilities of my Nikon D750, the detail is actually present:
When using such intensely capable cameras, it’s still a good idea to bracket if you have the time, as you’re often working with a very small window of exposure. And you may still wish to do exposure blending to maximize image quality. But this isn’t always necessary for a good shot, so I encourage you to experiment with your camera and determine what it can and can’t capture.
How to use dynamic range creatively
Low dynamic range scenes don’t offer many opportunities beyond the obvious: capture a well-exposed subject.
But high dynamic range scenes present you with a choice:
Use a strategy to capture the entire dynamic range of the scene…
…or embrace the loss of detail for a creative shot.
For instance, you might deliberately expose for the shadows and let the highlights go white for a bright, airy result. Or you might deliberately expose for the highlights and let the shadows go black for a moody, somber image.
Dynamic range in photography: final words
Hopefully, you now realize that dynamic range isn’t a tricky concept – and you know how you can use various techniques to capture beautiful images of HDR scenes.
So grab your camera. Find some HDR scenes. Practice capturing some photos. And have fun experimenting with post-processing!
Now over to you:
How do you feel about dynamic range? Do you like high dynamic range photos? Do you prefer to shoot in low dynamic range situations? Share your thoughts in the comments below!
The post A Comprehensive Guide to Dynamic Range in Photography appeared first on Digital Photography School. It was authored by Simon Ringsmuth.
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