Task 7 How to Use Smart Sharpen

New with Photoshop CS2, the Smart Sharpen filter offers more control than the Unsharp Mask filter. For example, Smart Sharpen allows you to sharpen more in the shadows than the highlights, or vice versa. In addition, Smart Sharpen includes alternative sharpening methods that go beyond anything Unsharp Mask could ever do.

1. Open the Smart Sharpen Filter

With your image open, select Filter, Sharpen, Smart Sharpen. The Smart Sharpen dialog box has a much larger preview pane than does Unsharp Mask, so you can safely disable the Preview check box if it slows down the preview refresh time. Set the Zoom to at least 100% using the + and buttons located under the preview pane.

2. Set the Amount Slider

The Amount slider determines how much sharpening is applied. As you increase this value, you increase the edge contrast added to the image. This is how the sharpening effect is achieved. However, higher values can also exaggerate noise and image grain.

3. Set the Radius Slider

The Radius slider determines the width of what Photoshop considers to be an edge (remember that sharpening works by adding contrast to edges). You should be as conservative as possible with the Radius slider because higher values add halos around image details. Lower is better here.

4. Set the Remove Method

Smart Sharpen provides three blur-removal methods, available from the Remove drop-down menu. Gaussian Blur works exactly like Unsharp Mask, whereas Lens Blur uses a more sophisticated algorithm to provide finer sharpening. Motion Blur assumes that the blur was caused by camera shake or subject movement and sharpens at an angle you specify. Although the More Accurate option increases the accuracy of all sharpening methods, it can be a drain on computer resources.

5. Set the Advanced Controls

When you click the Advanced option, the sharpening controls area displays three tabs. The Sharpen tab has the controls used in steps 24. The Shadow and Highlight tabs provide controls to fade the sharpening effect in their respective tonal ranges. On each tab, you can specify the Fade Amount from 0% (no fade at all) to 100% (no sharpening at all). The Tonal Width slider sets how much of the highlight or shadow range to fade. Radius defines the area used to identify a pixel as a highlight or a shadow.

6. Apply the Effect

Smart Sharpen uses navigation techniques common to most Photoshop filters, so clicking and holding inside its preview pane shows the unsharpened version. Releasing the mouse button restores the sharpened preview. Toggling this before/after view can be helpful. Click and drag inside the preview pane to shift the area displayed, or click in the actual image to center that section in the preview pane. When you've inspected the entire image, click OK to apply the effect.

How-To Hints

Selectively Sharpen

Smart Sharpen (or any sharpening method) can be constrained by selecting the area to be sharpened first with any standard selection technique. Alternatively, sharpen a duplicate layer and then use the Eraser tool or a layer mask to hide the areas you don't want sharpened.

Sharpen to a New Layer

Sharpening a duplicate image layer offers multiple advantages: It protects the original version so you can return to it later and allows multiple sharpness settings to be saved for different output purposes. And on severely sharpened images, the blending mode of the sharpened layer can be set to Luminance to eliminate color shifts along edges.