As long as cameras continue to improve in the quality of the images they’re able to produce, photographers will continue to push them to their limits. For that reason, every photographer will, at some time or another, be faced with a noisy photograph. What is noise in photography? What is noise reduction?
This article takes an in-depth look at noise and noise reduction. We’ll discuss what causes noise in digital photography and what you can do to get rid of it, both in-camera and in post-production.
What is noise reduction?
Before you can tackle the concept of noise reduction, it’s essential to first understand what noise is and what causes it. Similar to static over the airwaves or the “hiss” you hear when you record audio, noise is a series of grainy, random imperfections or abnormalities that appear in your digital photos. A small amount of noise is expected and acceptable in photography. The amount of acceptable noise is subjective and a topic of debate. However, when an image is thought to have too much noise, that’s when you’ll turn to noise reduction methods.
Types of noise
There are two main types of noise that appear in digital photography.
- Luminance noise. This is seen as irregularities in contrast in your photo and looks like grain. Luminance noise is a direct result of shooting in low light.
- Color noise. This is seen as random splotchy colored specks on your image. Color noise is much more unsightly than luminance noise.
What causes noise in photography?
Noise is a direct result of your ISO setting. The higher your ISO, the more sensitive your camera’s sensor. Therefore, the more susceptible it is to noise. As we mentioned above, every photograph will have some noise — it’s unavoidable. Fortunately, though, there are many options when it comes to noise reduction.
Tips to reduce noise
With the release of every new camera model, noise becomes less and less of a problem for photographers. Modern cameras are able to capture incredible detail in extremely low light situations. However, it’s important to know how to keep noise at a minimum so your photographs can be as crisp and clear as possible.
Here are tips for reducing noise, both in your camera when you’re shooting and how to get rid of it while you’re editing.
Noise reduction in-camera:
- Always expose correctly in-camera. This should go without saying, but a lot of photographers have a bad habit of over or underexposing their images and just figuring they’ll fix it later in post. Any time you push the exposure with software, you’ll amplify the noise. So, if your goal is to reduce noise, the best way to do it is to avoid capturing it in the first place.
- Shoot at the lowest ISO possible. As we mentioned above, a higher ISO means more noise, so always shoot at the lowest ISO setting you can.
- Shoot in Raw. When you shoot in raw, you capture the most information possible. While this may not directly reduce the amount of noise in your image, it will help immensely if you have to edit out noise later.
Noise reduction in post-production:
- Adobe Lightroom Detail Panel. If you use Adobe Lightroom (or Adobe Camera Raw), you’ll find some very helpful tools for noise reduction. First, adjust the Color Noise and Luminance sliders found in the Detail panel to achieve your desired look. Minor adjustments are key.
- Adobe Lightroom Blacks and Dehaze Sliders. Adjust the Blacks slider to reduce noise found in the dark parts of your image. Dehaze is intended for cutting out haze and fog in images, but it does a good job of noise reduction in the dark part of your images, too.
- Third-Party software to reduce noise. If you don’t find the built-in tools powerful or enough to do the trick or are looking for a simple option, there are plenty of third-party programs built specifically for reducing noise in images. Nik Dfine and Topaz DeNoise are two of the most popular.
- Image stacking. This very effective method to reduce noise is also quite time-consuming and relies on having multiple shots of the same scene. For those reasons, image stacking might not always be a viable option. However, it’s very popular in night photography and landscape photography, when you can plan ahead and take multiple shots. Then, combine them in Photoshop, removing the random noise from each of the layers and keeping the good data.
Technically, some amount of noise will always exist in every photograph. The amount you can accept is subjective but for the most part, when it comes to noise, less is more. Fortunately, there are many tools for noise reduction at your disposal. But remember, you’ll always get the best results when you minimize noise at the source.