Sharpening your images in post has been discussed time and again in every manner of tutorial under the sun, and everyone has a preferred method that works for them. For me, I found I enjoy the look of a partial sharpen done with the classic high pass filter (and requisite blending mode) along with an appropriate luminosity mask to blend it where I want it. These days I've gone and made an Action for the process that seems to work for about 80% of my images. Let's review it.
First off, if you've never done the high pass filter sharpening technique, then you should probably pay close attention to the beginning of the video above, or simply try YouTube in general for such tutorials. It really is quite commonly used, though some photographers loathe the look and prefer other sharpening approaches; further testament to the differences between artists and their styles of image crafting.
The basics of High Pass sharpening are as follows:
- Duplicate your main image (whether it's the background layer or a stamped copy later in your workflow)
- On the duplicated layer, run the High Pass filter (Filters/Other/High Pass) with a pixel radius setting between about 2.5 and 5, depending on your image overall pixel dimensions. (experiment with what looks good for you; more is not necessarily better).
- On the now High Pass filter-smothered layer, change the Blending Mode to Hard Light (a few other Blending Modes work too, but I find Hard Light to be the most consistent and predictable for the look I like).
- Boom, instant mega sharpen.
That's all well and good.
The issue, however, with High Pass sharpening are the side effects. The two most cited complaints about this look are that the sharpening is too strong overall, even at lower pixel radius settings, and that the highlights get messed up with noise and unnecessarily enhanced micro contrast. (Somewhere in the Comments section below, someone geekier than myself can and likely will explain why this occurs, along with all the maths and details of how the High Pass filter and Blending Modes work. As such, I'll let you scroll down the Comments for that info.)
To solve the two common complaints, I usually put a luminosity mask on the sharpen layer that masks out the highlights and allows the sharpening effect to transition from full tilt in the shadows to faded away by the mid-highs. I've reviewed this before using Color Range, which works ok. However, I prefer a more consistent result, and therefore I created an Action to set up High Pass sharpening the way I like: masked.
Check out the video tutorial above, and download my Smart Sharpen Action so you can test it out and let me know if it works for you.