How can I use CMYK values to white balance skin?

Question

I recently heard a photographer mention that they:

...adjusted the white balance using the CMYK method

I did a bit of searching on this and found different resources claiming to use formulas such as C+M+Y = 5 * K or that you need to have a certain percentage of each to have proper skin tones.

I'm more familiar with simply adjusting the white balance in Adobe Lightroom using the dropper tool on a grey or neutral part of the image. How would I adjust the white balance by the CMYK method properly in Photoshop(I am assuming you can't use this method in Lightroom)?

Answer 1

The guide I've always used is below. It differs by ethnicity, but is a good starting point. You can't use a dropper tool directly on skin because it's obviously not grey. Not if your subject is healthy

How to get pleasing skin tone

Highlights of the article:

• % of yellow should at least equal the % of magenta.
• Light skinned subjects should have between 5-20% more yellow than magenta
• Dark skinned subjects should have yellow and magenta very close
• Cyan should be between 30% and 50% of the magenta value

The article also describes how to use curves to sample and correct the color balance.