If you saw my video you know I use the high pass filter for more than sharpening.
I tried to find someone who could explain it better than me but I failed miserably and decided to give it a try (This is part of a full retouching tutorial I’m writing but that’s going to take some time)
In the Procces of retouching an image there are a lot of steps and this is NOT the first one, in the sample image there has been curves, levels, fixing of the background and diferent exposures of the raw, not to mention a lot of healing so, one more time…. this is just another step an to make that absolutelly clear:
…Now we are going to use high pass to enhance skin.
The High pass way is something like an automatic (not as detailed and not as undestructive) way of getting smooth but tight skin.
What we do is retain the edges of texture with the high pass, blur them a little (for the same reason we use a soft edged brush when Dodging and burning), invert them (to get the negative of the details light/shadow) and blend them linear light because this blending mode burns or dodges by decreasing or increasing the brightness, depending on the blend tone. If the blend tone is lighter than 50% gray, the image is lightened by increasing the brightness. If the blend color is darker than 50% gray, the image is darkened by decreasing the brightness (Very like D&B with a set of layers, that’s why I call this automatic D&B)
Now … you won’t be using this on the entire image, so what we do now is mask the whole thing out (Layer/layer mask/hide all) and then paint back with a white soft brush where it’s needed.
How to chose your radius?
We are always using numbers we can get 1/3 of (multipliers of 3) and it depends on what you want to D&B out of the image.
Small texture – radius of 3 or 6
Medium spots or holes in the skin – radius of 6 to 15 … maybe even 21.
Fix sudden change of light or general face features – Radius of 30 – 45 – 60
Find the problematic area / Chose your high pass / Gaussian Blur 1/3 of the HP radius / Invert (command/ctrl i ) Blend linear light / Mask to hide / Paint back where need it.
In the sample image I just used a 15/5 and a 45/15.
