Page 162 - Photoshop for Lightroom Users – Scott Kelby 2nd Edition

Step Five:
Okay, a better name for the next slider, the Bristle Detail slider, would be the Sharpness slider. It makes the overall image look sharper or softer with how it
affects the brush. Dragging it to the left takes away the detail of the brush bristles, so it’s very soft, smooth, and undefined. Dragging it to the right gives it
a harder, more detailed look that makes the image look sharper, as you really see the bristles in the stroke now. Compare the sky on the left (with the
Bristle Detail set at 1.0) to the one on the right (with it set at 10.0). It’s sharper, with more detail in the strokes.