There always seems to be an interest, as well as a bit of confusion, when it comes to color grading techniques. I’ve got a few emails where I was asked how do I get some color changes. Getting good color can sometimes be a difficult task, but like photography or painting, color grading is an art form that is best learned by doing.
What is color grading? Well, if you’re looking for a definition, it sounds like this: “Color grading is the art of manipulating color both for accuracy and emotional effect, usually performed by a colorist, who often plays a very large role in the look, feel, and emotional impact of an image”.
Here’s one image that I retouched few years ago. It looks like this (animated illustration here):
Since color grading isn’t an exact science, when doing it you may want to go back and forth with your changes – that’s why it’s very important to keep the effects on adjustment or separate layers, otherwise you won’t be able to do quick alteration or removal at any time during the color correction process. And if you need another reason to work non-destructively, keep in mind that adjustment layers can also be copied from document to document and this way it’s quite easy to reuse your favorite effects on other images.
There isn’t a single-best-of-all way to do it. It can be done with almost every Photoshop adjustment layer: Curves, Levels, Channel Mixer, Gradient Maps, Color Balance, Hue/Saturation, Photo Filter etc. It’s not about the tool you use, it’s about the result you get.
However, for the tools to work, you need to have at least a basic understanding of color theory – otherwise you may get some ugly color schemes that won’t do any good to your image.
Take a look at the color wheel below. You’ll notice the three primary colors in our RGB color wheel model: red, green and blue. Then, in between those you’ll notice the secondary colors of CMYK: cyan, magenta, and yellow. Secondary colors are formed by the sum of two primary colors: cyan is green + blue, magenta is red + blue, and yellow is red + green. Simple enough.
The secondary colors are opposite on the color wheel to the primary colors. Hence: Red – Cyan, Green – Magenta, Blue – Yellow. Another six tertiary colors are created by mixing primary and secondary colors, but we don’t need to get into that in detail right now. The primary and secondary colors + their relation to each other are the most important.
If you plan to use Curves adjustments layers to manipulate the colors of an image keep in mind that you can change the values of the red, green and blue channels separately. So, for instance, any adjustments upward of the diagonal line in the red channel increase the red in the image. Lowering, below the diagonal line, increases the cyan. The other channels are the same: upward in the green channel, green; lower, magenta. Upward in the blue channel, blue; lower yellow.
If you plan to use gradient maps, the easiest way to understand them is to look at the meaning of both words. Gradient – a gradient is a gradual blend between two or more colors. You can use gradients to create a photorealistic backdrop or to draw in areas like a blown-out sky. The Gradient tool is extremely flexible and offers the versatile Gradient Editor for creating custom gradients. Map – a map tells Photoshop how to assign or map colors based upon the luminance levels of the original image.
On its own the gradient map is pretty ugly, but toss in blending modes and you’ve really got some interesting results. This technique is one that encourages you to experiment. Be sure to fully explore the flexibility of the gradient editor and the subsequent variations of using blending modes.
Photoshop CS6 introduced a new adjustment layer called ‘Color Lookup’. This allows you to upload 3D lookup tables to alter colors and create specific looks. As the name suggests, a 3D lookup table is a matrix that uses one color to lookup another. They are the basis for a lot of color management and allow almost unlimited freedom in terms of color manipulation.
Photoshop comes with a handful of preset looks but has no mechanism for creating your own. Fortunately though, now that Creative Cloud is being pushed, it’s easy to take a quick peek at Adobe’s color grading software – SpeedGrade. Every color adjustments you make in SpeedGrade can be saved as a .look file or various formats of LUT, which Photoshop can load in the color lookup adjustment layer. It’s an interesting way to quickly package certain looks and use them the same way you would use any other adjustment layer.
While you can open, work on, and export still images in SpeedGrade, the software is designed for working on motion footage and it isn’t particularly efficient for photography, so you may want to keep your actions inside Photoshop. Nevertheless, there are a couple reasons why a photographer might want to spend a little time playing with it, especially if you’re already paying for it as part of Creative Cloud subscription.
Regardless the method you’ll choose to follow, always remember that one of the most important things to do when working with color is to take a break from time to time. Get up for five minutes, have a snack, and come back to your image with a fresh pair of eyes. You’ll be able to see things you didn’t notice five minutes before.