to paint this effect onto specific areas of your image.You can use the Sharpen tool to sharpen an image by enhancing medium and high contrast edges.
You can save your settings as a preset for future use.
To Sharpen an Image Using Sharpen Tool:
Click Reset to clear your changes and reset to default settings. If you saved your changes, you cannot reset your settings. If you want to discard only the Edit settings, select File | Restore to Developed.
Sharpen Options
|
Amount |
Specifies the amount of sharpening applied by increasing contrast around the edges. |
|
Radius |
Controls the number of pixels to adjust around each edge. Higher values increase the number of sharpened pixels and tend to bring out coarser detail, while lower values reduce the number of sharpened pixels and tend to bring out finer detail. |
|
Mask |
Allows the targeting of edges, while suppressing the sharpening of noise and texture. To view the areas the mask affects, press the ALT key when moving the mask slider. Areas affected by sharpening appear white. |
|
Detail |
Suppresses the halo, (the light border that forms around edges with extreme sharpening), by reducing its intensity. The higher the value, the stronger the reduction. |
|
Threshold |
Specifies how different the pixel lightness values within an edge must be before the pixels within the edge are sharpened. Higher values sharpen only stronger edges but minimize the appearance of noise. Lower values sharpen both strong and weaker edges, but can increase the appearance of noise. We recommend you set the threshold to enhance edges while keeping background noise to a minimum. |
You can right-click a slider to reset to the default value.
You can use the Edit Brush to paint this effect onto specific areas of your image.
You can use the Gradient tool 
to transition this effect across specific areas of your image.
You can use the Radial Gradient tool 
to apply effects around, or directly to, a center point.