What is noise reduction in photography – Lightroom tips 2023

Using noise reduction in Lightroom Classic has helped me so many times when I’ve had to photograph a wedding in a dark church, or when photographing past sunset. So, noise reduction is great if you can’t avoid image noise in the first place at time of capture. But what is noise reduction in photography and how do you reduce noise in Lightroom?

In April 2023 Adobe Lightroom made a few changes to Lightroom Classic that is very useful for photographers who regularly have to deal with noisy photos. Adobe added Denoise AI to their noise reduction tools. And it’s seriously impressive!

What’s even better than noise removal is reducing the possibility of image noise in photos as much as possible before taking the shot. I’ll go into this briefly, but will link to a detailed article I wrote on image noise so that you don’t have to rely on noise reduction more than necessary.

So, in this article we’ll look at:

  • What is image noise in photography
  • What is noise reduction in photography
  • How to avoid adding noise during editing
  • Noise reduction in Lightroom Classic
  • How to avoid noise in photos

What is image noise in photography?

In digital photography noise looks a lot like grain in film photography, so instead of referring to a digital image as grainy we say it’s a noisy image.

Noise in digital images shows as the speckling of pixels that makes a photo look a little rough. It’s more obvious in the darker areas and out of focus areas of an image.

If there isn’t a lot of noise in an image you might not notice it, but when you zoom in closely on the computer, digital image noise becomes much more visible. With a noisy image, however, noise is very obvious, even without zooming in.

sunset beach portrait edited with Lightroom noise reduction

Subtle luminance and color noise reduction applied in Lightroom Classic.
Camera settings: 1/1250, f3.2, ISO 500. Taken at 8.25pm in the last rays of sunlight. I had to use a high shutter speed to freeze motion, so had to increase the ISO. 

Different types of noise in photos

There are two types of digital noise in photos:

  • Luminance noise
  • Color noise (aka chromatic noise or chroma noise)

Luminance noise is the more common type of noise and shows up as light and dark speckles in both light and dark areas of photos. Luminance noise affects only the brightness of pixels.

Color noise affects pixel color and shows as speckles of color (mainly red and green) in the dark areas of photos.

We’ll take a closer look at avoiding noise in a moment. First, here’s how to fix it with noise reduction software.

What is noise reduction in photography?

Photographers use noise reduction to remove noise from photos in post processing software. While the appearance of noise is reduced, the catch is that you lose sharpness in photos.

There are many ways to remove noise from photos online free, and there’s good editing software you can buy, like Topaz Lab’s DeNoise AI. However, Lightroom Classic is largely preferred by professional photographers.

Now, moving on to actually fixing noise in images with Lightroom noise reduction.

 

SOOC image next to Lightroom edited image with noise reduction

On the left is the image straight out of camera and on the left is the edited image with noise reduction, but in the process some noise was added to the image, as you’ll see further down.

Avoid adding noise in the editing process

When you brighten an underexposed photo in Lightroom by increasing the exposure slider you’ll increase the visibility of noise in an image.

If you increase the shadows slider instead of the exposure slider there’s less chance of introducing noise to an image during processing.

How to reduce noise in Lightroom Classic

You’ll find the Lightroom noise reduction tools in the Detail Panel towards the bottom on the right side of the Develop Module in Lightroom Classic.

When using the Lightroom noise reduction tool it’s best to zoom in to 100% as this is when the image noise is most obvious. Lightroom actually shows a little warning if you don’t.

Use noise reduction in photography sparingly. When an image has a little noise and only a small amount of noise reduction is needed, it works very well. Even quite noisy images can get good results.

However, when you start making big adjustments in noise reduction problems creep in. Noise reduction software is not a miracle cure, even with the advances in editing with artificial intelligence. Too much noise reduction makes an image look super smooth and plasticky. You’ll lose sharpness and the image will look sort of out of focus.

Each image will require a different amount of noise reduction, so you’ll need to experiment to get the right look each time.

Noise reduction panel in Lightroom Classic

Global noise reduction in Lightroom

You now have three global noise reduction options in Lightroom Classic post production that’ll affect the whole image:

  • Denoise AI 
  • Luminance sliders
  • Color sliders

Lightroom denoise AI noise reduction

While Denoise AI is working a moving circle appears next to the Denoise button.

Lightroom Denoise AI

Denoise AI is Lightroom’s artificial intelligence update to their noise reduction tool, while the sliders are for manually adjusting noise.

To use Denoise AI click the Denoise button in the Noise Reduction panel.

An Enhance Preview dialog box will open and your picture will begin loading. 

Lightroom denoise AI dialog box

The default Denoise AI amount is 50 and you can change it if you wish.

Enhance preview Lightroom denoise AI dialog box

If you’re happy with the amount of Denoise AI applied, click the Enhance button. You’ll notice that Lightroom gives you an estimated time for the action to take place.

Lightroom denoise AI enhance preview

Once complete the Denoise AI panel will add text to alert you that denoise AI has been applied to the photo.

Lightroom denoise AI panel

When denoise AI has been applied Lightroom creates a new DNG file of the image and stacks it with the original file.

In the film strip you can see that it’s stacked and a denoise AI badge is added to the thumbnail – the black box with the 3 white stars.

Filmstrip image with badge indicating Denoise AI used

The new dng file is renamed with the text “Enhanced-NR” added to the end of your filename.

Lightroom denoise AI dng file name

Close up of image showing before and after Denoise AI noise reduction in Lightroom

Above is a close up of the image showing before (left) Lightroom Denoise AI noise reduction and after (right) using the default settings.

Luminance noise sliders in lightroom
Default luminance noise reduction settings on the left and on the right you can see that the detail and contrast sliders become active once the luminance slider is moved.
 

2. Luminance noise reduction in Lightroom Classic

As luminance refers to the brightness of an image, the luminance noise slider adjusts only the brightness of pixels.

Of the two sets of noise reduction sliders, luminance noise is the one we adjust most of the time.

There are three luminance sliders for luminance noise reduction in Lightroom. By default the luminance slider is set to zero and the detail and contrast sliders are grayed out until you add luminance noise reduction.

The default luminance noise sliders and settings are:

  • Luminance: 0
  • Detail: 50
  • Contrast: 0

The detail slider helps you to keep some of the detail you lose when applying noise reduction. Again, you need to use this sparingly so that you don’t push it too far.

The contrast slider adds back some contrast that gets removed in luminance noise reduction. This returns some of the sharpness to the image.

Subtle noise reduction in Lightroom

Above are the noise reduction settings I used in Lightroom Classic. (This is what the noise reduction panel looked like before the 12.3 update. The only change is that instead of it saying Noise Reduction at the top, it now says Manual Noise Reduction.)

Before and after too much luminance noise reduction in Lightroom

Above left is a close up of the photo without noise reduction and above right with maximum noise reduction, which made the skin look like plastic.

Maximum noise reduction settings in Lightroom

I pushed both the luminance slider and the color slider to maximum to show you the effect.

Before and after automatic color noise reduction in Lightroom

On the left is the image with the automatic color noise reduction removed and you can see speckled flecks of green and magenta. On the right is with it applied.

3. Color noise reduction in Lightroom Classic

Lightroom automatically adds a level of color noise reduction on import, but you can also make further adjustments if you wish.

When a color appears to have a mass of red, blue, green and magenta dots, instead of being solid, what you’re seeing is color noise. The color noise reduction sliders are below the luminance reduction sliders in the detail panel and are almost the same.

The default color noise slider settings are:

  • Color: 25
  • Detail: 50
  • Smoothness: 50

Instead of a contrast slider, in color noise reduction, there’s a smoothness slider, which is exactly what it does. Again, be careful you don’t go too far, because Lightroom noise reduction will already have smoothed the image a bit automatically.

Use the detail slider to add detail back in.

WARNING: If you push color noise reduction too far, you’ll lose some of the natural color variation in your image.

Before and after too much color noise reduction in Lightroom

I brightened the image to make the noise more obvious. On the right the you can see how too much color noise reduction ruins the color in an image.

Local noise reduction in Lightroom

Use local noise reduction in Lightroom to reduce noise in certain parts of an image, instead of the global adjustment that’s made with the noise reduction sliders and Denoise AI.

Open the mask tool, select the type of mask you want to use and then select Noise from the drop down menu.

Lightroom noise reduction mask menu

When you create a mask to reduce noise in images, you can’t choose to adjust either luminance noise and/or color noise. Lightroom will automatically reduce luminance noise only with masking. You can however adjust the noise slider amount as well as the mask amount to control how much noise reduction is applied.

Lightroom noise reduction mask sliders

Aside from that, local noise reduction works the same way as global noise reduction in Lightroom.

The most useful Lightroom noise reduction masks are:

 

Online Lightroom workshop for professional photo editing

 

So far we’ve covered what image noise is and noise reduction in Lightroom Classic, and I’m sure the process will be similar with other photo processing software. But it’s better to avoid noise in photos in the first place.

I’ve written a detailed explanation of image noise and how to avoid it, which you’ll find helpful. However, here’s a brief look at how to avoid noisy images. 

What causes digital noise in photos?

The truth is that you can’t be entirely free of noise in photos, even if you think you’ve avoided it. To avoid getting overly technical about image noise, the noise level that I’m talking about is where it becomes obvious in a photo and starts to ruin image quality.

Noise in photos can be caused by underexposing in low light conditions, long exposure times and also as part of the editing process.

It’s not always possible to avoid noise in images, but you can avoid it as much as possible with:

  • Correct camera settings to avoid underexposure
  • Add light to the scene

A third option is to use a full frame camera rather than a crop frame camera if you regularly photograph in low light situations. A larger camera sensor captures more data than a smaller sensor. However, don’t rush out and buy a new camera until you’ve tried my noise reduction tips.

1. Camera settings for best results

If you can avoid noise to start with, you’ll spend less time in post production removing unwanted noise with noise reduction software.

In-camera noise reduction

Did you know that you can reduce noise in-camera?

Not all digital cameras have this ability, but it’s certainly worth checking if your camera model does. If you have a higher end camera, you’ll have in-camera noise reduction and will be able to set it through the menu settings.

Exposure settings to avoid noise in photography

If you’ve come across any discussion on image noise, you’ve no doubt heard that it’s caused by high ISO settings.

Well, that’s not entirely true.

Noise is far more obvious in an underexposed image with a low ISO brightened in post than than a correctly exposed image with a high ISO. When you increase the brightness of an underexposed image in editing software, the noise becomes obvious.

So you need to ensure that your subject is correctly exposed for how much light is available with either a:

  • Longer shutter speed
  • Wider aperture
  • Higher ISO (as a last resort)

Increase the ISO only if you can’t set a slower shutter speed or wider aperture. 

Photograph in RAW format

Before moving on from camera settings to avoid noise, there’s one more you need to know about. It won’t help you to avoid or reduce noise, but it will help in the editing process to get a better final image with noise reduction.

For photos with less noise is to photograph in RAW file format rather than JPEG file format. If you want to reduce image noise in post production, RAW files will give you much better results. Not much detail is retained in JPEG images, because they’re processed in camera, which strips away data.

underexposed dancer at beach compared to with flash lit image

Add light to illuminate the subject rather than capture an underexposed image.

2. Add light to avoid noise in photography

If there’s not enough light available for an accurate exposure of the subject, you need to add light to the subject with:

  • Artificial light – flash or continuous light
  • A reflector to bounce light back onto your subject

To be precise, what we’re talking about is the signal to noise ratio, or SNR. The signal is the light recorded by the image sensor that forms an image.

If you can’t see the signal (image) clearly, because it’s underexposed, a higher level of noise will be visible when you increase the brightness of the image in post production. The signal to noise ratio is low.

A well exposed subject has a lot more light than noise, even with deep shadows and bright highlights in the image. So the signal to noise ratio is high. For this reason, high contrast images with a high dynamic range don’t appear noisy when exposed correctly.

Noise reduction in photography wrap up

So, now you know that you can’t entirely remove noise from photos, but you can reduce it to the point of not being noticeable, because you can:

  • Work to avoid image noise when you take the photo
  • Reduce noise in images, to an extent, with noise reduction software

As each photo, or series of photos, is different, you’ll need to assess if noise reduction is necessary and if so, how much, on a photo by photo (or series) basis.

Try to get it right in camera and capture an image as you intend it to look straight out of camera with small editing tweaks, rather than relying on fixing an underexposed image in post.

Leave a comment

If you have any questions about how to reduce noise in images, let us know in the comments.

Also, I love good news, so if my Lightroom noise reduction tips have helped you to understand how to reduce noise in Lightroom Classic, share that too.

1 thought on “What is noise reduction in photography – Lightroom tips 2023”

  1. Excellent summary of a topic that is usually not well understood. The information on Lightroom Classic is very useful, especially the discussions of what to do and what not to do.

    Reply

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