Photoshop USM Sharpening

Feel PS inside the USM very good, there should be many we do not find the method, this I have long wanted to put forward, here I said a few I often use the method, I hope you have any comments, you can propose research, if you have and I different methods, no matter how simple and complex, also sent out to share analysis

USM Tuning Method 1:

What questions can be made, I try to answer

USM Tuning Method 2:

Now this USM Tune 3, I think the best is also my favorite, the effect is very good, a lot of advice

Correction: Method 3 That, turn back to RGB, copy only one layer, not two layers

The bottom layer is the background layer.