Sharpening and Noise Reduction

Get more information on Photoshop sharpening and Photoshop noise reduction features in this free lesson.

Introduction

Video: Sharpening and Noise Reduction

Launch "Sharpening and Noise Reduction" video!

Photoshop includes several tools you can use to correct your images. In this lesson, we'll show you how to make the following corrections:

We'll also talk about the importance of using these tools correctly. If they are misused, sharpening and noise reduction can actually cause problems with your images. However, if they are used with care, they are a great way to add polish to your images.

If you'd like to follow along, you can download some or all of our example images. Just click any of the images below to open a full-sized version. Then right-click the full-sized version and select Save Image As to save it to your computer.

image of hawk
image of building
image of ferris wheel
image of flower

Sharpening

Sometimes an image may not be as clear as you'd like it to be. Sharpening can help to make your images look crisp and clear by enhancing the edges of objects in the image. However, adding too much sharpness can actually make an image look worse, or it can lead to a loss in image detail. Take a look at the example below:

images comparing varying levels of image sharpness

As you can see, the right amount of sharpness makes the photo look crisp—for example, in the center image, it's easy to see the edges of the bird's feathers. But adding too much sharpness can cause the edges to look exaggerated and unnatural (these are known as halos), as in the image on the right. You may have also noticed that the background in the oversharpened image has a lot of added image noise, or graininess. We'll talk more about reducing image noise on the next page.

Whenever you apply sharpening, you'll need to look critically at the image to see if you're getting the results you want. You'll often need to make careful adjustments to get the right amount of sharpening without introducing other problems like halos or noise.

Drag the slider in the interactive below to adjust the sharpness of the image. Try to make the image look crisp but not oversharpened.

Unsharp mask

The unsharp mask filter is a common way to sharpen images in Photoshop. When you use this tool, you'll be able to control a few different settings, including:

To apply an unsharp mask:

  1. Right-click the layer you wish to sharpen, then select Duplicate Layer. You'll apply the sharpening to this duplicate layer, which will prevent you from accidentally altering the original.
    Screenshot of Adobe Photoshop CC
  2. A dialog box will appear. Type a name for the new layer, then click OK. In this example, we'll call it Sharpened.
    Screenshot of Adobe Photoshop CC
  3. With the new duplicate layer selected, go to Filterright-arrowSharpenright-arrowUnsharp Mask. If you're using Photoshop Elements, you'll need to go to Enhanceright-arrowUnsharp Mask.
    Screenshot of Adobe Photoshop CC
  4. A dialog box will appear. Set the desired radius size, then choose the amount of sharpness to add. We recommend experimenting with different amounts of sharpening to see what looks best. You can look at the preview window above the sliders to see how sharpening is affecting the image.


    Screenshot of Adobe Photoshop CC
  5. Click the preview window to toggle the preview off and on. This is an easy way to compare the sharpened version with the original. To view a different part of the image, you can click and drag within the preview window. Note that you'll also see the preview in the main document window.
    Screenshot of Adobe Photoshop CC
  6. Continue to adjust the settings until you're satisfied with result, then click OK. The unsharp mask will be applied.

Open the hawk_fullsize.jpg example file, duplicate the background layer, and apply an unsharp mask. Adjust the settings to find a balance between sharpness and a loss of detail.

If you want to learn even more about sharpening, check out this tutorial from Cambridge in Colour.

Sharpening tips

Here are a few tips for getting the best results with sharpening:

Screenshot of Adobe Photoshop CC

If you want to learn more about using Smart Sharpen, check out the Sharpen Your Photos with Smart Sharpen video on the Adobe website.

Noise reduction

Some images may have a lot of noise, which causes them to look grainy. You can compensate for this by reducing the image noise, as in the example below:

images demonstrating noise reduction

Understanding noise reduction

When you apply noise reduction, you're actually removing information from the image. As a result, you'll need to use this feature carefully—removing too much noise can result in blurriness and a loss of detail. The goal of noise reduction is not to completely remove all noise from the image; instead, you're just trying to make the image look cleaner and clearer.

As with sharpening, you should always look critically at the image to see if you're getting the results you want. Losing a small amount of detail may be unavoidable when reducing noise, so you'll need to make careful adjustments to find the right balance. It's often better to remove less noise in order to preserve as much detail as possible.

When you use this tool, you'll be able to control many different settings, including:

Drag the slider in the interactive below to adjust the level of noise reduction. Remember, removing too much noise will cause the image to lose detail. Try to find a level that makes the image look clean without losing too much detail.

To apply noise reduction:

  1. Right-click the desired layer, then select Duplicate Layer. You'll apply the noise reduction to this duplicate layer, which will prevent you from accidentally altering the original.
  2. A dialog box will appear. Type a name for the duplicate layer, then click OK. In this example, we'll call it Noise Reduction.
  3. With the new duplicate layer selected, go to Filterright-arrowNoiseright-arrowReduce Noise.
    Screenshot of Adobe Photoshop CC
  4. A dialog box will appear. Take some time to adjust each setting, following the guidelines above—you can look at the preview window to the left of the sliders to see the effect.
    Screenshot of Adobe Photoshop CC
  5. Click the preview window to toggle the preview off and on. This is an easy way to compare the noise reduction with the original. To view a different part of the image, you can click and drag within the preview window. Note that you'll also see the preview in the main document window.
  6. Continue to adjust the settings until you're satisfied with the results, then click OK. The noise reduction will be applied.

Open the globe_building_fullsize.jpg example file, duplicate the background layer, and apply noise reduction. Adjust the settings to find a balance between noise reduction and a loss of detail.

Challenge!

If you want to practice making the adjustments we cover in this lesson, you can download some or all of our example images. Just click any of the images below to open a full-sized version. Then right-click the full-sized version and select Save Image As to save it to your computer.

image of hawk
image of building
image of ferris wheel
image of flower
  1. Open the flower_fullsize.jpg example file in Photoshop.
  2. Duplicate the background layer, then apply an unsharp mask. Take some time to adjust the different settings, comparing the sharpened version with the original.
  3. Open the ferris_wheel_fullsize.jpg example file.
  4. Duplicate the background layer, then apply noise reduction. Take some time to adjust the different settings, comparing the noise reduction with the original.
  5. When you're finished editing, use the Save for Web feature to export the images as JPEGs.