Quick links to procedures on this page:

•
 
To sharpen an image by applying a filter
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To sharpen selected areas by applying brushstrokes

Sharpening images

You can sharpen images to increase contrast, enhance image edges, or reduce shading. To sharpen an image, or an editable area of an image, you can use filters or brushstrokes. Filters can also be applied using a lens. For more information about lenses, see Working with lenses. Sharpening is usually done after adjusting the color and tone of an image and after resampling or resizing.

You can reveal more image detail by sharpening an image.

To sharpen an image by applying a filter Back to Top
1.
 
Click Image Correction Tune sharpen.
2.
 
Move the Percentage slider to set the amount of sharpening that is applied each time you click a thumbnail button.
3.
 
Click any of the following thumbnail buttons:
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Unsharp mask — lets you accentuate edge detail and focus blurred areas in the image without removing low-frequency areas.
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Adaptive unsharp — lets you accentuate edge detail by analyzing the values of neighboring pixels. This filter preserves most image detail, but its effect is most apparent in high-resolution images.
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Sharpen — lets you accentuate the edges of the image by focusing blurred areas and increasing the contrast between neighboring pixels. Move the Background slider to set the threshold for the effect. Lower values increase the number of pixels changed by the sharpening effect.
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Directional sharpen — lets you enhance the edges of an image without creating a grainy effect.

You can also
 
Remove shading
Click Effects Sharpen High pass. The High pass filter removes image detail and shading to give an image a glowing quality by emphasizing its highlights and luminous areas. However, it can also affect the color and tone of the image.

The Unsharp mask filter provides best results for most photographs.
Most sharpen filters support all color modes except 48-bit RGB, 16-bit grayscale, paletted, and black-and-white. The Sharpen filter supports all color modes except paletted and black-and-white.
You can access each of the sharpen filters individually by clicking Effects Sharpen, and clicking a filter.
You can use this procedure to sharpen an editable area of an image.
To sharpen selected areas by applying brushstrokes Back to Top
1.
 
In the toolbox, click the Effect tool .
2.
 
On the property bar, open the Effect tool picker, and click the Sharpen tool .
3.
 
Choose a brush from the Brush type list box.
4.
 
Choose a nib from the Nib shape picker.
5.
 
Type a value in the Size box to specify the nib size.
6.
 
Drag across an image area.
You can quickly choose a square or round brush shape by clicking the Round nib button or the Square nib button on the property bar.
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