Noise Reduction Tutorial

Noise Reduction Tutorial using Adobe Lightroom and Photoshop

Ever take an underexposed image, open it in Lightroom, correct the exposure level, only to be greeted with the sight of horrible digital noise? You then try to reduce the digital noise but end with a waxy and unnatural looking photo. Hopefully this tutorial will solve those problems. This is my method of reducing digital noise in a photo without giving the entire image a waxy look that destroys the details.

You will need Adobe Lightroom and Photoshop for this tutorial.

Open the image you want to modify in Adobe Lightroom. After you make all the light and colour adjustments to your image go to the Detail panel and locate the Luminance slider under Noise Reduction.

detail panel

If you’re using a RAW image leave the Sharpening slider at 25 default. If you’re using a jpeg leave the Sharpening at the 0 default. Raise the Noise reduction slider to the point where the image, especially in the dark areas, is waxy and poorly defined.

detail panel

Right click on the image and select edit in Photoshop. The image will now be opened in Photoshop.

Right Click
Go back to Lightroom and reduce the Luminance slider to anywhere from 0 to 10. Follow the same steps as previously to open the image again in Photoshop. You will now have two different images open in Photoshop. Zoom in to 100% so you are sure which one is the Noise Reduced image.

This is the image WITHOUT Noise Reduction.
This is the image WITHOUT Noise Reduction.

Then press cmd+A (MAC) or ctrl+A (PC) to select the entire image (you should see the “dancing ants” as pointed by the arrows), then cmd+C or ctrl+C to copy the image.

Selected Image
Selected Image with tell tale waxy look of Noise Reduction

Go back to the image without noise reduction and press cmd+V or ctrl+V. Photoshop automatically creates a new layer that will go on top the original layer.

Layers Panel
Layers Panel

If you cannot find the layers panel go the the menu on the top of Photoshop, select Windows and scroll down to Layers.
Windows Menu Photoshop

Toggle the little eye to see the differences between the two layers, but make sure the eye is back on before the next step.
on-off

Click on the Channels tab to open the Channels tab. Hold the cmd or ctrl key and click on the thumbnail image titled RGB.

Channels panel
Channels panel

You should see a selection (or dancing ants) on the image.

Channel Selection
Channel Selection

Go to the menu at the top of Photoshop and find Select. From the Select menu select Inverse.

Selecting the Inverse
Selecting the Inverse

No go back to the Channels panel and switch the tab back to Layers. Look for the rectangle with a hole in it at the bottom of the Layers panel. This makes a layer mask. Click on it. You have created a layer mask.

Mask button
Mask button
Mask
Mask

It should look like an inverted Black and White image. To see the mask properly alt+click on the little black and white thumbnail in the Layers menu.

Hold down the alt key and click.
Hold down the alt key and click.

The mask will show up in the main display area. What is happening is the black areas of the mask are hiding the lighter areas of the waxy noise reduced layer while the darker images are still being displayed. At this point you may want to make some refinements to your mask. Go the Image section of the top menu and select Adjustments, then Levels.

levels3

Levels control
Levels control

Bring the black and white sliders inwards and adjust the middle slider depending to taste. The darker the mask the less of the noise reduced image will be visible in the final edit.

Refining the levels of the mask.
Refining the levels of the mask.

Once you have made adjustments click OK to exit Levels and then alt+click on the mask thumbnail to leave the mask and return to the main image. Click on the little eye to turn off the noise reduced image and view the original image without the noise reduced layer. Make sure to turn it back on before the next step.

Go the the little side menu in the Layers panel, open it, and select flatten image.

little menu

flatten

This will combine the two layers into one. This is why it’s important to make sure both layers are on. Next save the image as the default TIF file.

save

It should automatically open in Lightroom and you can make further adjustments as required.

Here are the original images and the final image for comparison. The light areas kept the detail while the darker areas are much smoother. Unfortunately the uploading compression has reduced the quality of the image.

Image with no Noise Reduction
Image with no Noise Reduction
Image with heavy Noise Reduction.
Image with heavy Noise Reduction.
Final image after combining the two images.
Final image after combining the two layers.