How Sharpening Works

To sharpen an image, choose Filter > Sharpen. Photoshop presents a submenu of choices (Figure 6.26) on which the top three options might sound friendly (Sharpen, Sharpen Edges, and Sharpen More), but you might want to ignore these techniques; they’re simply presets that enter different numbers into the bottom choice, Unsharp Mask. The bottom two filters in the list are the only ones that allow you to control exactly how much the image will be sharpened. We’ll start by exploring the Unsharp Mask filter and then refine your knowledge by exploring Photoshop’s Smart Sharpen filter.

Figure 6.26. Photoshop’s sharpening options.

Unsharp Mask has this confusing name because way back before people used desktop computers, they ...

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