Enhancing Local Contrast
Many images appear more punchy if improvements are made to local contrast (also known as microcontrast). Most contemporary RAW editors have microcontrast tools built in. ACR and Lightroom use the Clarity setting in the Basic adjustments panel to adjust microcontrast, and the effect this produces is very different from that produced by conventional contrast tools.
You can achieve similar effects in Photoshop by using the Unsharp Mask filter with a low Amount setting (between 20 and 40) and a large Radius value (between 30 and 60).
This technique can cause unwanted alterations to saturation. You can avoid these by applying ...