Photoshop How To … High Pass Filter Correction
If you like photographing people as much as i do … you’re probably going to use some sharpening method. I favor using a High Pass filter on a copy of the original and setting the blend mode to overlay (you can change the layer blending mode prior to using the filter, allowing you to see the actual change the filter will inflict on your image).
The High Pass filter works as a sharpening tool by selectively increasing contrast in an image . One should be aware that when bumping up the filter amount it will spawn colors in areas of high contrast, colors that will bleed through and contaminate your other layers.
This can be fixed by using a Black & White filter clipped to the High Pass … or simply desaturating the filter (i like the first method because it gives me more control and is non destructive).