Instead of applying a low pass filter, also known as the gaussian blur filter, we'll be using the Surface Blur filter instead. Select the Filter> Blur menu and choose Surface Blur. The surface blur filter blurs the image but preserves the edges. It is great for smoothing skin without losing the edges. The Surface Blur provides two options:
First, set the radius and threshold so that the image becomes blurry but still recognizable. Then, lower the Threshold and stop just when the edges become sharp. Now adjust the Radius so that the skin is smooth.

We're done with the Low Pass layer. Now we'll work on the High Pass layer that'll restore the tiny details such as the bumps and pores. Select the layer, click on the eye beside the High Pass layer, and change the layer blending mode to Linear Light.
The tiny bumps of the skin is most visible on the neutral tones of the skin and least visible on the dark tones of the skin. To simulate this natural effect, we'll add a layer mask that will reduce the visibility of the bumps on the darker tones of the image. Add a layer mask by clicking the
button or by going to the Layer> Layer Mask menu and selecting Reveal All.
