Publishers of technology books, eBooks, and videos for creative people

Home > Articles > Design > Adobe Creative Suite

  • Print
  • + Share This
This chapter is from the book

This chapter is from the book

Sharpening Images

Most images can benefit from sharpening, which enhances the edges by increasing the contrast of adjacent pixels. Photoshop includes several filters that sharpen areas of an image. Which filter you use depends on whether you need to sharpen all or only part of an image, and how much control you require. No matter which method you use to sharpen an image, be careful not to oversharpen. Sharpening brings out the detail in images, but it can't compensate for severely blurred images.

Here are some tips for sharpening images:

  • Always work with a duplicate of the image, so you can return to the original if you aren't wild about the changes you've made. Additionally, you can convert layers to Smart Objects and then use Smart Filters to sharpen them.
  • Create a duplicate layer and apply sharpening to that layer, so you can turn it off if you need to sharpen differently later. If you work with a duplicate layer, use the Luminosity blending mode for the best results.
  • Save sharpening for the last step, when you're just about to optimize your image for the Web or prepare to print it. The exception is if you need to sharpen to correct some blur caused by the camera or scanner; that sharpening should occur at the beginning of your workflow.
  • The Sharpen, Sharpen Edges, and Sharpen More filters are automatic. The Smart Sharpen and Unsharp Mask filters give you more control.

Smart Sharpen

The Smart Sharpen filter performs multiple tasks at once. In addition to sharpening edges, it reduces noise. You can choose whether to apply the filter to the entire image, its shadows, or its highlights.

You can also choose which algorithm the filter uses to sharpen the image:

  • Gaussian Blur uses the same algorithm as the Unsharp Mask filter; it increases the contrast along the edges.
  • Lens Blur detects edges and detail; it sharpens finer detail without adding many halos.
  • Motion Blur removes blur that was caused by the movement of either the camera or the subject of the photo. If you choose Motion Blur, you also need to specify the angle for the blur.
Figure 4.25

Figure 4.25 The Smart Sharpen filter gives you control over the way Photoshop sharpens your image.

To use the Smart Sharpen filter:

  1. Zoom to 100 percent or greater so you'll see an accurate preview of the sharpening.
  2. Choose Filter > Sharpen > Smart Sharpen.
  3. Select an option from the Remove menu to determine which algorithm is used to sharpen the image.
  4. Keep an eye on the preview window as you adjust the Amount and Radius sliders. The Amount slider determines how much sharpening occurs; the higher the amount, the greater the contrast between edge pixels. The Radius slider determines how many pixels surrounding the edge pixels are affected by sharpening.
  5. Select More Accurate if you want Photoshop to process the file more slowly, resulting in a more accurate sharpening.
  6. If you want to adjust the sharpening of shadows and highlights separately, click the Advanced button to display additional tabs. The settings on the Shadow and Highlight tabs let you reduce halo artifacts.
  7. Click OK when you're satisfied with the sharpening.

Unsharp Mask

It sounds like it ought to blur the image, or make it "unsharp," but the Unsharp Mask filter actually sharpens images. Its name comes from a traditional darkroom technique, in which the original blurry negative of the image was overlaid with an attempt at sharpened edges, and a final print was created from that.

The Unsharp Mask filter removes Gaussian blur by increasing the contrast along the edges: it makes the dark areas darker and the light areas lighter. The filter determines which pixels to darken or lighten based on the pixels near them. The radius determines how large an area the filter compares. If you go too far with sharpening, you'll probably see a halo effect around the edges.

Figure 4.26

Figure 4.26 Use the Unsharp Mask filter to sharpen the edges in an image.

To use the Unsharp Mask filter:

  1. Choose Filter > Sharpen > Unsharp Mask.
  2. Select the Preview option if it's not already selected. When Preview is selected, you can preview the filter results in the full image window. Just deselect Preview to compare the sharpened image with the original.
  3. Set the Radius value. Unless you're going for a dramatic, artistic effect, keep the radius pretty low, usually between 1 and 2 pixels.
  4. Adjust the Amount slider to increase or decrease the contrast. For high-resolution printing, Adobe recommends 150 percent to 200 percent.
  5. Set the Threshold value. The threshold determines how different the pixels must be from the surrounding area to be considered edge pixels. The default threshold, 0, sharpens every pixel in the image. For most images, you'll do best with a threshold between 2 and 20.
  6. Continue adjusting the sliders until you reach a combination that works for your image, and then click OK to make the change.
  • + Share This
  • 🔖 Save To Your Account

Peachpit Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Peachpit and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about Peachpit products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites; develop new products and services; conduct educational research; and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by Adobe Press. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive:

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020