Foolproof frequency separation for perfect skin retouching.

In this tutorial, we will give you an easy, foolproof way to get perfect frequency separation without making your subject look fake or plasticky. In addition, we've included a FREE Photoshop Action download that does all the work for you.

Skin is one of the most important parts of your portraits to retouch, and when it is done poorly, portraits can look like wax figurines. This is generally due to the lack of skin texture and wrinkles, which is fixable by applying frequency separation correctly.

Two-layer approach

Our foolproof method for perfect frequency separation uses two layers, a high frequency layer for sharpening and correcting minute details plus a low frequency layer that uses blurring to blend color tones evenly. When used together with the right technique they give you the perfect retouch.

In the high frequency layer, you will use cloning and healing to clean up harsh blemishes and stray hair - that's the simple part for anyone who knows Photoshop.

The low frequency challenge

The more challenging part however is how much blurring effect to use on the Low Frequency layer to achieve perfect tone blending. Use too little and you wasted your time, but use too much and you get fake, plastic-looking skin. 🤮

Figuring out how much blurring effect to apply varies from image to image due to image size and cropping. For example, if your image has a low resolution, a blur of 10 pixels has a much more dramatic effect than a high resolution image. So determining how much blur effect to use is always a riddle.

The answer is the Magic Number

The Magic Number always gives you the foolproof amount of blur effect to use on your Low Frequency layer no matter what resolution you image is, or how cropped in to your subject's face you are. It will always achieve a clean and smooth skin effect, and most importantly it will make skin look natural without the use of heavy healing or cloning.

To do it, download our FREE Frequency Separation Photoshop Action  and follow the steps below.

1 - Install and play the Action

2- Determine your Magic Number

1. To get your MAGIC NUMBER you have to measure the pixel height of the face
2. Select the Marquee tool (hit the "m" key - the tool icon is a box with a dashed outline)
3. Then drag a box around your subject’s face. While dragging, pay attention to the pixel HEIGHT (H) of the face
4. Next, take the last 2 digits off and that's your MAGIC NUMBER. For example: H: 1082 px, take off the last two numbers & you get a MAGIC NUMBER of 10
5. After you get your MAGIC NUMBER remember it!

3 - Create layers & filter

1. Duplicate Skin Base 2 times
2. Name the top one "High Frequency for Clone Healing" and the one below it "Low Frequency for Blurring Color"
3. Turn off the High Frequency layer
4. Select the Low Frequency layer, and go to Filter > Dust & Scratches
5. Enter your MAGIC NUMBER in the box for Radius while leaving the Threshold at 0
6. This creates the foolproof amount of blur no matter what your image size or how cropped into your subject's face you are

4 - Blend skin tones to smooth

1. In the Low-Frequency layer, select the Lasso Tool (hit the "L" key)
2. Set FEATHER equal to your MAGIC NUMBER
3. Draw shapes over areas of the skin where you want to smooth out color tones
4. For each shape you draw, go to Filter>Blur>Gaussian Blur and use the same amount of your MAGIC NUMBER
5. Keep drawing shapes and blurring until you have the desired result
6. Be careful not to do too much or it will flatten out the subject - you can always go back and blend more later

5 - Spot heal blemishes

1. In the High-Frequency layer select the Spot Healing Brush (cycle Shift+J) or Clone Stamp Tool (cycle Shift+S)

2. If cloning make sure Sample is set to Current Layer
3. Zoom in very close to see pores of the skin
4. RIGHT CLICK YOUR BRUSH to set the size no larger than a few pores
5. Set BRUSH HARDNESS TO 100% or you will lose detail in skin texture
6. Make small dabs, lines and/or shapes over blemishes and stray hairs
7. Focus mainly on the parts of the blemishes where there is the most contrast

5 - Zoom out and review

1. Zoom in and out to determine if everything looks good
2. You can do more cleaning up by going into each layer and continuing previous steps

LensLab Frequency Separation Action Completed

1. Click Continue to flaten the SKIN REPAIR folder and rename it SKIN REPAIRED.
2. If you did too much and your subject looks fake or flat, discard the layer and re-run the action.