Advanced Color Correction Part One

requires version 4

This is a continuation of Tutorial #10 taking the same image and making further corrections. The image at the far left is where we left off in the previous tutorial, the second image after the steps in this tutorial have been made. While the skin tone is within the acceptable range it isn't what it should be yet which is betrayed in two areas, the hair and shirt both having a orangish-red shading.

With the new Color Corrector filters it is now possible to make very fine adjustments that previously were more difficult in earlier versions. The actual makeup of the shirt should be stripes of very dark brown, nearly black, alternating with a medium chocolate brown. This is what we'll try to adjust to and in the process the hair color, skin tone and background will be pushed into the correct range in the process by using two filters new in version four: Color Corrector and Color Corrector (Secondary).

Since we're already close to where we want to be we'll use the color wheels in free style mode and not use the eye droppers which would likely shift colors further off rather then nudging them to where they should be. Because I know what color the shirt should be that makes the job easier. If I didn't know then I would try to key off the hair and get as close as possible by observing the effect on the skin tone. In this example the left ear is plainly visible, so we'll keep an eye on the upper ridge, watching that it continues to have the characteristic blush.

Keen observers may catch something odd about the position of the color wheels, in that they are all shifted to cooler shades, yet the image is warmer. So what's going on with that? I also used the secondary color corrector.

While the main purpose of the secondary color wheel is to adjust a single color in an image you can also use it to further refine what you do with or main color corrector wheels. I slowly rotated through the hues settling on a plus 16 value then shifting the chrominance wheel to the values you see. This settings will alter all tonal values if you do not select a specific color. The values you see in the main color wheels are the results of shifting them a little more than where they were previously. So to boil it down, I added to the hue (top slider) to get the hair color where I wanted it, then balanced off towards cooler shades to bring out the blue in the background while watching that I kept the shirt stripes in their proper range without getting the skin tone too pink. The controls in both Color Wheels are very sensitive, so a very small adjustment can have a major impact. Also notice that I tweaked the saturation level in both filters, also increasing the gain and gamma. This is a good time to mention the benefit of using an external monitor to make these kind of adjustments. Viewing off your computer monitor, and now viewing this Tutorial from a web browser simply don't show the same shades as you'll see on a television. Close yes, but better on the external monitor.

What I've found useful as a guide is when watching my external monitor, boost the saturation level to a point where it becomes obvious you're just a bit over saturated, then drop the saturation level back down in tiny nudges while tweaking the Gain and Gamma settings, while observing both the histogram and waveform to be sure you're within legal bounds. The doing is much easier than in sounds in describing it.

The goal with tweaking Gain and Gamma is to further increase brightness and contrast just a little without distorting the histogram, again a little if any is all that's needed. Note the slight glow in the cheeks and shine to the hair while the shirt remains flat.

If you find yourself making large adjustments with these setting the problem is more likely something wrong with overall distributions of pixels better corrected with Color Curves.