How do I reduce noise in my photos?

What is noise in digital photos?

Noise in digital photography refers to random variations and imperfections in the image signal or brightness levels. It often appears as colored speckles or grainy texture in an image (source).

There are two main types of noise:

Luminance noise: Seen as grainy texture across the image, especially in dark areas.

Chroma noise: Multi-colored speckles, most visible in areas of uniform color.

Noise is caused by factors like long exposures, high ISO settings, hot image sensors, and the camera’s internal processing (source). The longer the exposure and higher the ISO, the more noise is introduced. Noise has a major impact on image quality and perceived sharpness.

How does noise affect image quality?

Noise can have a significant detrimental effect on the quality of digital photos. Excess noise reduces detail and apparent sharpness in an image (Unveiling the Lens and Sensor Symphony: Decoding Image). Areas of an image with noise will appear grainy, blotchy, and lacking in fine details. The noise can end up obscuring finer textures and edges that would otherwise be visible. This loss of detail is especially noticeable in large prints.

Noise can also be visually distracting and undesirable in a photo. The randomly scattered brighter pixels stand out and interfere with the overall clean appearance of the image. Excess noise draws the eye away from the main subject and compositions elements of the photo. In many cases, noise is considered an artifact that degrades the aesthetic quality of the image (Development of a Super-Resolution Scheme for Pediatric). Reducing noise can dramatically improve the visual impact of photos.

What camera settings contribute to noise?

Two main camera settings that contribute to noise in photos are high ISO settings and long exposures.

Using a high ISO setting, like ISO 1600 or higher, can introduce noise into your photos. The higher the ISO number, the more sensitive the camera’s sensor becomes to light. However, higher ISO settings also amplify noise that is inherent in digital sensors. According to Digital Photography School, shooting at lower ISO settings like 100 or 200 can help reduce noise (source).

Long exposure photos, where the shutter is open for an extended period of time, can also lead to noise. When the shutter is open for more than a few seconds (like in night photography or light painting), sensor noise has more time to build up and can become visible in the image. Using a noise reduction filter, as recommended by Adobe, can help minimize noise in long exposures (source).

How can I avoid noise while shooting?

One of the best ways to avoid noise in your photos is to use the lowest ISO setting possible for your shooting conditions. The lower the ISO, the less noise will be present in your images. Try to keep your ISO at 100 or 200 if there is sufficient light. Only increase the ISO if you have no other way to get a properly exposed photo without using a very slow shutter speed.

When shooting long exposures, use a stable tripod to avoid shake and blur which can be mistaken for noise. Long exposure shots tend to generate more noise, so a tripod is essential for minimizing this effect. Lock your camera securely on the tripod and use either a remote shutter release or the camera’s self-timer mode to take the photo without touching the camera. This will ensure your long exposure shots stay sharp and noise-free.

Noise reduction software

Using post-processing software is an effective way to reduce noise in photos. Popular options like Adobe Lightroom and Photoshop plugins offer sophisticated noise reduction capabilities.

Lightroom has built-in noise reduction tools that allow you to reduce luminance and color noise. The noise reduction slider under the Detail panel can help smooth out graininess and splotches of discoloration. There are also more advanced noise reduction controls under the Color Mixer and Calibration panels. Using these tools together enables customized noise reduction while preserving image details.

For more aggressive noise removal, Photoshop plugins like DxO Nik Dfine and Topaz DeNoise AI utilize more advanced AI and machine learning algorithms. These can eliminate noise while retaining sharpness. Many photographers rely on such plugins for dealing with high ISO noise and very grainy images. Overall, noise reduction software provides powerful options for cleaning up photos.

Noise reduction in Lightroom

Lightroom provides effective tools for reducing both luminance and chroma noise in photos while preserving image detail. The Noise Reduction sliders can be found in the Detail panel in the Develop module.

Luminance noise appears as graininess or speckles across the image and is most visible in shadow areas. The Luminance slider targets luminance noise specifically. Dragging it to the right will smooth out luminance noise. However, pushing it too far can result in a loss of image detail, so it’s best to use restraint.

Color noise shows up as random red, green and blue speckles or blotches. The Color slider targets color noise. Increasing it reduces color speckling, but can also desaturate colors in your image if you’re too aggressive. It’s helpful to zoom in at 100% magnification to better see the noise while adjusting the sliders.

In addition to Luminance and Color, the Detail slider can help control the level of detail preserved when applying noise reduction. Moving it to the right helps maintain edges and details like hair or foliage. Overall, it’s a balancing act between reducing noise and maintaining natural image detail and sharpness. Subtle application of the sliders usually produces the best results.

For more tips, see this guide on optimizing the Noise Reduction tools in Lightroom.

Noise reduction Photoshop plugins

Photoshop offers some excellent plugins specifically for reducing noise in photos. Two of the top plugins are Neat Image and Dfine. These plugins use advanced algorithms to analyze the noise in an image and apply targeted noise reduction without sacrificing detail.

The main advantage of using Photoshop plugins over Lightroom for noise reduction is the level of control and customization available. With plugins, you can finely tune the settings and target specific areas to preserve detail. Lightroom’s noise reduction tools work well for basic overall noise reduction, but plugins give you more advanced options.

Plugins like Neat Image and Dfine also excel at reducing high ISO noise from shooting in low light conditions. The noise analysis and pattern matching capabilities can dramatically reduce grain and shadows while maintaining a natural look. For best results, Photoshop plugins should be used as part of an overall post-processing workflow alongside Lightroom.

Other noise reduction tips

There are a couple other tips for reducing noise in your photos besides using noise reduction software:

Image averaging

Image averaging involves taking multiple exposures of the same scene and then averaging them together. This allows random noise to be canceled out while real detail is reinforced. To use this technique, you need to take shots on a tripod so they line up perfectly. You’ll get the best results with around 10-20 exposures.

Noise generators

Some advanced noise reduction techniques actually involve adding controlled noise back into an image after the original noise has been reduced. This can help avoid an overly smooth, plastic look. Plugins like Topaz DeNoise AI have options to add realistic noise back into areas like skies.

When to use noise creatively

While noise is generally seen as a flaw, there are instances when adding noise deliberately can be used for creative effect. Photographers may add noise post-processing to give images a gritty feel or to make them feel more analog. Adding noise can also lend a sense of mystery or moodiness to an image.

Noise can work particularly well for black and white photos. The graininess evokes the feel of film photography and adds texture and visual interest to what might otherwise be a flat black and white image. As John Paul Caponigro notes, “Grain in a black and white print adds texture and detail. It can enhance the feeling of resolution and sharpness.” Used artfully, noise can emphasize key subject details and add atmosphere.

Additionally, some photographers add noise to give portraits a grittier, more authentic look. Rather than aiming for perfection, embrace imperfections like wrinkles and blemishes. As Contrastly discusses, noise in portraits “shows subjects as they really are” and makes them feel more real and human. When used deliberately, noise can produce images with a raw, authentic vibe.

Key takeaways

Here are some of the key takeaways for reducing noise in your photos:

Use low ISO settings whenever possible to avoid introducing noise while shooting.
Expose properly and avoid underexposing, which can increase noise.
Use noise reduction software like Lightroom or Photoshop plugins to clean up noise in post-processing.

Apply noise reduction gently to avoid losing image detail.
Use noise creatively for artistic effect in some situations.
Invest in low-noise camera bodies and lenses to maximize image quality.

Following proper camera technique and using noise reduction tools selectively allows photographers to minimize noise while maintaining image quality.