[Rob Barron]

I think Steve's idea is intended for a final touch, not for the main sharpening of a picture.

It is simply not possible to give a set of numbers for the settings and use them for every picture as all shots are different. It's rare I use a high figure for radius as that would then only sharpen areas of very low detail. For people, I would start with a small radius value, a 0 threshold and only about 100% but will then go up from there to what the picture needs. The problem is often hair as that will show over-sharpening before skin ever will, especially if it is curly or wavy hair where it will have a smiliar effect to moire patterns.

If you find you are getting the hair over-sharpening but the skin is not as sharp as you'd like, lift the threshold and this will have a counter-balancing effect so as the threshold goes up, the sharpening will come down a bit. Then you can push the radius higher without over doing the hair.

If the picture is a landscape with no or little delicate detail, set the radius a bit higher, try around 10. Setting this higher will help to reduce sharpening of any noise in the sky which can end up looking granulated. I do the same with stonework that has intricate convolutions like a sculpture.

The key is of course to experiement and try what works best. But always watch areas of high contrast as that is where you will get the dreaded halo effect that ruins a good picture. Just don't assume that because a setting worked for your last picture that it will be the same for this one.

Having said that, if you took a lot of photos of a similar object, it is likely that you will need much the same level of USM so then you can apply it without going through the dialogue box. All you have to do is hit Ctrl+F and it will apply the last filter you used (I am assuming you are not applying lots of other things in between here!). If you feel it has applied a touch too much this time, just press Ctrl+Shift+F and you can reduce the effect by sliding the percentage down until it reaches the point you like.

Ok, I'll shut up now. I really do go on don't I? <g>

Cheers,
Rob