Let me add one thing to what Suzie said.
I have found that the "De-Fog" USM setting I like so much (20 - 60 - 0) will sometimes introduce a distracting halo. Not always; it seems to be more pronounced if part of your image is against sky (blue sky, not blah white or gray sky). I finally stumbled into doing exactly what Suzi said: Open image, duplicate layer.
After you apply USM 20-60-0 to the duplicate layer, look to see if any halo was created. If so, either use a mask to block that thin, bright rim, or do what I usually do: take the eraser tool, get a pretty small brush size, and carefully remove the halo.
Rusty
I have found that the "De-Fog" USM setting I like so much (20 - 60 - 0) will sometimes introduce a distracting halo. Not always; it seems to be more pronounced if part of your image is against sky (blue sky, not blah white or gray sky). I finally stumbled into doing exactly what Suzi said: Open image, duplicate layer.
After you apply USM 20-60-0 to the duplicate layer, look to see if any halo was created. If so, either use a mask to block that thin, bright rim, or do what I usually do: take the eraser tool, get a pretty small brush size, and carefully remove the halo.
Rusty