Frequency Separation is a technique that was once a closely & jealously guarded secret used by high end professional portrait retouchers in their work.
It is called Frequency Separation because an image is separated into a High Frequency & Low Frequency layer. The high frequency layer contains the texture while the color and tone is in the low frequency layer. This technique allows us to work on the texture or color / tone layer without affecting the other layer.
In this 14m 8s YouTube video tutorial, Aaron Nace of PHLEARN fame demonstrates this technique & shows us why it is so amazing & powerful for portrait retouching. Aaron keeps the training nice & simple so that it is not too intimidating.
You will need Intermediate to Advanced Photoshop skills to follow along.
Summary for the busy person
God bless Aaron, the 3 notes in his post are the summary!
IMPORTANT: When editing a layer with the healing or clone stamp tool, ensure sample is Current Layer (11m 25)
- Getting Started with Frequency Separation (If done properly, nothing seems to have changed)
- Make 2 copies of the image
- Apply Gaussian Blur to the Low Frequency layer
- Apply Image to the High Frequency layer
- Layer: Low Frequency layer
- Blending: Subtract Scale:2 Offset:128
- Change Blending mode to “Linear Light”
- Correcting Underlying Color (Low Frequency layer)
- Edit by selecting the areas of skin for smoothing with Gaussian Blur (feather the selection / check with Quick Mask ‘Q’)
- Correcting Texture (High Frequency layer)
If it is too complicated, Aaron has automated the steps for creating the 2 layers in an action which you can download.
A good productivity tip: create keyboard shortcuts for frequently accessed functions.