The Local tab sheet controls the local contrast effect. The local contrast effect often appears less strong than the dynamic and adaptive contrast effects, but it can effectively emphasize edges and compress the contrast range to enrich the mid tones.
The Arrow-Down Button
Clicking on the arrow-down button will display a menu with various local presets. These local presets are useful settings for the controls of the current tab sheet. Each tab sheet has its own arrow-down menu with different presets. Only the "Reset" option is the same. It sets the controls of the tab sheet to their default values.
The Intensity slider is only available in Local Contrast mode. In Expert Mode it is replaced by the Local slider on the Mix tab sheet. The Intensity adjust the intensity of the effect. A slider value of zero means no effect and a slider value of 100 applies the effect at full intensity.
The Radius slider adjusts the size of the details that are emphasized. Low slider values focus on small details in the image whereas high slider values bring out the contrast in large details. The unit of the slider is not pixels, but a percentage of the image size. So the same Radius value will produce the same effect for images of different size.
The Compress slider moves the shadows and highlights toward the midtones, which effectively means that the shadows will be brightened and the highlights will be darkened. It makes the image look more evenly lightened. It may produce halos in some cases, which can be softened with the Soft Light slider.
The Expand slider works contrary to the Expand slider. It makes the highlights brighter and the shadows darker. It brings out details in image edges.
The Soft Light slider modifies the effect of the Compress and Expand sliders. It can soften the harshness of both effects and make the local contrast effect look less flat. Using a middle value is often the best choice for it.
The Shadows slider lets you brighten up the shadows areas. It depends on the local contrast effects, so it does not work like the Shadows slider on the Dynamic and Adaptive tab sheets.