This is a great Photoshop technique I picked up a few years ago. I'm always trying new things, new plugins, software, but I always seem to come back to the High Pass filter as my favorite sharpening trick. And it works really well on Landscape and HDR Photography.
Lately my two combo punch as been to use Define 2, part of the Nik Collection, to remove noise, then the High Pass filter to sharpen.
Since using Dfine 2 is literally just pushing one button, I won't go over that.
Sharpening With The High Pass Filter
You can do this technique at any stage in your process. A lot of people like to do it towards the end.
If I'm just coloring with basic curves and nothing destructive I might do it first so I can have a better see the details of my photo.
Step 1) Create Stamp Visible Layer And Duplicate
So the first thing you want to do in Photoshop is create a Stamp Visible Layer.
Do this by selecting your top most layer and press pushing Command+Option+Shift+E. (Ctrl+Alt+Shift+E on PC)
If you're doing this technique first, then ignore that first part as you'll just be duplicating your background image.
Then you can duplicate that layer. (Command+J) or (Ctrl+J on PC).
Step 2) Use The High Pass Filter
Now we'll go up to Filters->Other and set the High Pass Filter.
Step 3) Adjust Radius
Now you'll adjust the radius of the High Pass filter so that the edges and details are barely visible. If you do this too much you'll get that halo sharpening effect around your edges. So keep it low if you can. This will also depend on how sharp your images is to begin with.
Step 4) Set The Blending Mode To Linear Light, Overlay, or Soft Light
Once you've created this grayed out looking layer, you'll want to set the blending mode to Linear Light, Overlay, or Soft Light. Which ever you prefer.
The difference is, Linear Light will give you the most detail, sometimes too much detail. You can dial it back by using Overlay or Soft Light. It's really up to you.
Our Before And After
This is a 100% crop on the image so you can see the difference. Try to look past the web compression.
The effect works great.
Step 5) Stop Here, Or Duplicate Layer
If you're happy with the results, you can stop here. But usually I like to duplicate this layer at least once, sometimes twice. But duplicating too much can reveal some noise and grain.
Command+J (Ctrl+J) To Duplicate.
On this second layer I'll often set it to Overlay or Soft Light so the sharpness isn't to exaggerated. But it's up to you and every image is different.
Here is what that looks like 100% Cropped.
You'll see a bit of grain appear in the water in the image above. That's because this was an HDR photo so you'll see more of that tonemapped grain. Usually doing a noise reduction pass before using the High Pass filter will fix this. But if it doesn't you can throw these layers into a group and apply a layer mask. Then you can brush out all the areas on the layer mask that you don't want sharp. It works really well. But using Layer Masks will be a completely different tutorial.
Final Landscape Photo – 'Good Promises'
Camera Used: Sony A7r
Lens: Rokinon 14mm
Bracketed -+2EV 3 Shots