As a Beauty & Fashion retoucher, one of the tools I most often go to is the Healing Brush tool. It works similarly to the Clone Stamp tool in the sense that you choose the area that you wish to source from, but it comes with some interesting features of its own.
The main attraction to the Healing Brush tool is the ability to transfer the texture of one area to another. It does this while simultaneously blending the color and luminosity that is sampled from the edges of your replacement selection.
Take these two sample swatches as a demonstration.
Generally you should source from similar texture to the one you are replacing, but I am using both different texture and colors to better illustrate how the Healing Brush tool works.
The square on the left is filled with yellow high contrast large grain texture, while the one on the right is with lower contrast small grain texture.
While sourcing from the right and placing my brush like so, gives this result:
You can see the texture has been replaced, while leaving the original color and luminosity the same.
When clearing skin from blemishes and hairs, this allows more possible areas to be used to source from, while also producing a more seamless replacement than might have been possible using the Clone Stamp tool.
You can also see that in the lower portion of the circle that’s been healed a dark area has blended like a gradient into the spot. This is because the rim of the brush is used to source the surrounding area’s luminosity and color to be averaged and blended.
To show this more clearly, refer to the images below.
A bright pink line is added to both swatches, with how the Healing Brush is placed shown:
And the result:
You can see the blending effect of what is sourced around the brush here clearly.
However, if we source from a section of the blue swatch where the pink line is also intercepting, and align it correctly with the line on the yellow swatch, like so:
You will see the Healing Brush more or less is unaffected by the line, and replaces the rest of the texture without color or luminosity bleeding into the healed area:
The same approach is used when trying to heal next to a high contrasted area or border, such as a nose bridge, jawline, ears or any other area where you would like to keep a border from blending into the healed area.
While the Stamp Tool can be used in smaller strokes to replace an area gradually, the best results when using the Healing Brush tool are achieved when the entire problem area is covered and replaced in one go.
However, in order to help the tool make averages of the color and luminosity, using a smaller brush than the problem area, and making a squiggly yet precise shape over what you would like replaced works better than a larger brush size that covers the whole area. This is due to the increased surface area the outline of the healed area is exposed to, giving the tool a better chance to properly blend the areas together.
Similarly to the Clone Stamp tool, a hard edge brush should be used to retain the most texture. A soft edge brush produces the effect by blending and fading out the edges into the rest of the image, so over time if you’re not careful it can lead to a slightly blurred and splotchy effect.
However, using a brush at 100% hardness is not ideal either, as you might be able to see the border from where the healing was done. Somewhere around 75% hardness seems to work best.
Keep in mind that shadows are generally flat with little contrast, and highlights have a fair bit of contrast and detail in them. This means that when sourcing, be sure to pick a spot with relatively similar levels of focus and lighting.