A few years ago I was talking with a fellow photographer about the color correction of portraits. While on the topic of using white balance cards and color charts in order to get a perfect skin color, he interrupted me and said, “You can't have perfect skin color with these.” I immediately thought to myself, “Oh, yeah?” Oh, yeah. That was the truth, and I will explain why below.
I remember my first photographs with a point-and-shoot camera in a room lit by tungsten light bulbs. The resulting pictures were with a dominating yellow color. Someone told me then: “You have to fix your white balance.” That was the first time I heard about such a correction. The white balance is an overall color shift tool in the digital world. You can set it in your camera or in a post-processing software. The proper way of setting a white balance is by using a white balance card and snapping a frame with it filling a big portion of the frame. You can use a white sheet of paper if you don't have such a card, and although it will take you in the ballpark, it won't be absolutely correct.
If you want to go further in the journey for a perfect color, get a color correction chart. Using such a chart helps you fine-tune the different color hues for your camera and lens combination. Your color will be almost perfect with just a white balance card, but with a color correction chart the photographs will be altered with minute color adjustments, and thus reaching the color-perfect goal.
Perfect Doesn't Mean Perfect
“But in the introduction you said you can't have a perfect skin tone regardless of the perfect color calibration,” you might say. Technically speaking, your color will be perfect in theory after these two steps, but when you look at people's skin in the following photographs, you will find there are color deviations, and sometimes they are quite big.
Imagine me, knowing my color was perfectly dialed-in, banging my head, because on my color-calibrated monitor the skin sometimes looks way differently than it was in the real world. I would calibrate the monitor again, I would create new color profiles, adjust the white balance from the white balance card, but the color would be off.
Below is a fresh example from a photoshoot of several people and you can clearly see that skin colors have different hues; some look fine for a Caucasian person, others look either more yellow or too pink. The picture looks creepy, but once you think about the technical side of it, the creepiness goes away. You can see that the white of the eyes looks normal thanks to the white balance card, but skin color in real life for some of those people looked more natural than on the photographs. You may tell me that “It's OK to have different skin hues for each person,” and you will be right. The problem I'm trying to solve here is when the skin on the photograph is very different from the skin color under the environment conditions you saw it with your eyes. In these examples the camera settings are the same, the lighting is the same, the white balance is all set using the white balance card.
Skin Is Not a Piece of Textured Color Paper
If you are photographing objects like paintings, fabric, and paper, the chances of having a perfect color are bigger. The reason lies in the type of texture you work with. When you calibrate your colors using a color chart or a white balance card, you are taking a photograph of a surface that doesn't have the layers, glossiness, transparency, texture, and all other properties of the skin. You are photographing a flat colored matte material. The tools that help you dial the white balance in guarantee that the colors of the flat matte material of the color chart will be white indeed. Nobody promises anything about other surfaces. That's where I got fooled believing the skin color would also be perfect.
Skin is a multi-layered thing that has lots of characteristics. If you have worked with 3D or had chance to see how skin texture is artificially designed you will understand some of its complexity. Each skin layer has color, transparency, moisture, elasticity, and texture. These properties are different on different parts of the body, and different for every human being.
When you light a multi-layered object like skin, the reflected light changes because of these properties. We are able to see objects because of the reflected light. We perceive colors by the colored light that is reflected from the surfaces. The more the moisture, the more specular highlights and the more contrast the skin will have. Some skin is more transparent and have more of a light red, light yellow, or light brown hue. Some skin reacts in a different way to some light color hues than others. When you light skin with different light sources (hard or soft) and from different directions, it changes the hue because light penetrates the layers from different angles and is reflected in a different way towards the lens.
How to Have a Perfect Skin Color Then?
Unfortunately you can't automatically have a perfect skin color, but you can have a color that is pleasing to your eye or the eye of those who will receive the photographs. There's no such thing as a “perfect color,” but there is such a thing as “a color that is close enough.” Of course, for artistic purposes you can have whatever color hue you want in the final result.
My approach is first to get the color in the ballpark using the white balance card and (sometimes) the color correction chart. For a white balance and color correction chart I use the Color Checker Passport. Since I switched from Lightroom to Capture One Pro, I can't use the color profiles created by the Color Checker software in Capture One, and I'm only using the white balance card tool. I photograph a picture with the color chart in frame, and for this particular product the white balance card is a square from the grid on the left of the chart.
In my post-processing software of choice, I go to the white balance tool and click in the square marked in the picture above. This sets a correct white balance for the colors on the chart, and hopefully it's close enough for the skin of the majority of people you will photograph on the set. If your software supports synchronizing of the white balance setting, you can copy it on all images from your series. Now it's time to judge by eye if there's a significant color shift from the skin color you think is normal, and try to color correct only the hues of the skin color, whether using global or local adjustments tools.
I won't talk in details how this is achieved, because there are excellent articles on perfecting the skin tone in post-processing software written by fellow writers at Fstoppers. You can choose to read those that match your current workflow. Know that it's OK to manually tweak skin tones in post even if you have used automated tools for calibrating your color.