Unsharp Mask is an intelligent sharpen filter used to make an image look more crisp. The filter defines pixels where two areas of contrast meet and increases the contrast of those pixels. Finding the "perfect setting" is not a science in Unsharp Mask. Each image can require radically different settings. Experiment with the settings until you find the one that is right for the image you're adjusting.
The Depth slider controls the threshold of the effect. The lower the value, the greater the effect. The smaller the number, the more defined the edges will be. The Intensity slider controls how strong the effect will be. The Breadth slider controls the amount of used when testing areas for changes in contrast.
