Use both sliders to pull out contrast patterns. Using the Enhance Detail slider only brings out image detail. Using the Smooth Detail slider only smooths image features. When you use both sliders you are smoothing the smallest contrast variances and the largest, so you are pulling out contrast patterns.
I have created 8 variations of this image to illustrate this effect. The slider values are given in the image description to the side of the image. The very last examples (Variation #7 and #8) demonstrate processing the image twice with Lucis.
1) To get a more striking image have the slider values very close together (difference between the two sliders = 2 to 6). If you do this and make the values of the sliders low, you create a very textured image which can be add texture to the original image. Just use the Mix With Original Image slider.
2) Checking the Tie Together check box on the Lucis Pro User interface keeps the two sliders a fixed value apart so when you move one slider the other follows. This makes it easier to explore the image variation possibilities. You have to Uncheck the Tie Together check box to make the difference between the two sliders a different value.
3) When using both sliders is is best to set the number of Processing Scan Lines to 40. It will take longer to process the image but the result will have fewer radial artifacts, if any.