I'd have taken the layer opacity some % down but that's taste. I'm always using the high-pass hattrick these days but the problem is usually not the sharpening itself but the oversharpening.
It's very easy to use too much. What I do is bring the opacity down while switching the layer on and off until I have a hard time seeing the actual difference. Then I up the % a couple. I do that for all three layers.
What you also have to pay attention to is to erase undesired auras. Especially the outlines in high contrast areas can suffer those artifacts (the tail of the second as an example displays a fine "glow"). I simply use the eraser and remove those parts in the high pass layers before merging all.
The using too much is what bothered me,i think its like eating curry you start with a mild one but can quiet easily start craving stronger tastes,will start playing with the eraser
Interesting - my response didn't post!
What I've found with HP sharpening is that it's very easy to overcook it, and hard to judge when you're in the Filter dialogue and wondering precisely what radius will be most effective for your image.
I do not apply this until after resizing (and have pretty much given up on it in favor of Smart Sharpening for web images), but when I use it this is what I do...
1. Open the resized image in Photoshop
2. Duplicate the background layer
3. Set the Blend Mode on layer 1 to Overlay or Vibrant (the first if I want mild sharpening, the other if I want it really sharp).- This now looks like crap, but fear not...4. Zoom to 100% (cmd/cntrl-1)
5. Under the Filter -> Other menu, choose High Pass
6. Making sure Preview is checked, adjust the Radius until the proper effect is achieved.
7. Move the Opacity slider to 20% and then bring it back slowly until it looks right. More times than not I stop around 80%.
I do about the same but think my PS version has a slightly different high pass.
None of the three layers ever has more than 40% opacity and vivid seldom more than 30%. But since every next layer shrinks the high-pass range by 50%, the effect is much more sensible than using only one high-pass layer.
It might be different for newer PS versions.
I have elements 11 so it may be different again
I posted this on another thread a few weeks ago. This video gives some really good practical tips on sharpening. Its worth watching all the way to the end for the final technique. The subject is not birds as such but the same methods apply.
https://www.youtube.com/watch?v=YOeZD8ZKCjQ