The Language of Color in Photography

The Language of Color in Photography

 

Many moons ago I worked as a scanner operator for a large printing company. This was back in the day when printing plates were created using huge sheets of film that were captured with scanners and cameras the size of two rooms with a massive lens in the wall between them. Understanding colour and using the right language to describe it, from a technical perspective, was critical to being a successful scanner operator, and has also been in part one of the keys to my success as a full time professional photographer.

 

DC350_0092As a scanner operator I was responsible for separating a photographs colours so that film negatives were created that could be used to create the plates for large printing presses. You had to carefully mount the images on a large drum, then spin it at a high speed while a light source read the colour values and simultaneously reproduced each of the printing colors onto film. That film was then combined with others in a process called film stripping to create the printing plates.

Scanners were complicated and expensive machines. The array of dials, knobs, meters, and scales were daunting to the novice operator. You really had to understand the language and science of colour to the nth degree to use this machine, and it took years to master. Today, the old scanners are yet another relic of our digital age, yet many of the controls that ran these old analog scanners are embedded in the software settings we use in our image editing today, such as Photoshop. What hasn’t changed however, are the basics of colour theory, and more importantly the language of colour in photography.

Understanding and being able to communicate the correct language on any subject is important to most of us. However describing color can be a challenge. On one occasion while working as a scanner operator, an artist told me he wanted “more moxie” added to his painting. He even used hand signals to show that what he wanted was “bigger”. I had to tell him there was no moxie dial or setting and I needed a better explanation. What he really meant was he needed more saturation.

 

The following is my simplified way to describe color using a 3 dimensional space model.

 

Imagine a cylinder that you can look into, and every color that we can see with our eyes is visible and represented by every space inside it. If you hold the cylinder and turn it you could see where all the colors are, that they have a logical order, and are arranged in such a way that can be described and understood.

Now imagine a 100 story cylindrical building with a glass elevator right in the center with stops on every floor. The elevator shaft represents Lightness, a key term when describing color. Lightness has also been called Brightness, Luminosity, Luminance, Shade, or Value. Get inside the elevator at the ground floor and you’ll notice that everything is black. There is no color, just pure black, a Lightness of 0. Press the 100th floor and as you progress up the elevator, the black turns into a dark gray, then becomes progressively lighter until you’re on the 100th floor when all you see is pure white. The elevator has progressed through the Gray Tones. This has also been referred to as the Gray Scale. From black, and progressing through the Gray Tones up to white there is an absence of any color.

Now at the bottom floor of this cylindrical building imagine that the very outside edge is painted with the colors red, blue, green, yellow, purple, and orange. These pure colors are called Hue, another key term when describing color. Each of these hues is arranged on the outside of the building in a specific way, red, orange, yellow, green, blue, then purple.

As you rise up the building from the outside, the Lightness of the Hue increases so that it is 50% lighter on the 50th floor than it was on the ground level when it was at it’s darkest. By the time you get to the 100th floor the Lightness of that Hue is almost pure white. As you progress up the side of the building the Hue changes from a pure color, lets say red, up to a very light pink.

Starting from the elevator on the ground level, walk towards the outside edge towards the pure Hue of blue for example. You’ll progress from a Lightness value of pure black, progressing through a dark gray blue, then getting progressively more blue with less black, until you get to the pure Hue of blue on the very outside edge of the building.

Progressing through this dimension you are passing through Saturation, the last key term for describing color. As you walk towards the pure Hue, the Saturation increases reaching 100% at the outer wall. It still retains the same amount of Lightness on each floor of the building. Saturation is also referred to as Chromaticity, or Chroma.

Each floor of the building keeps the same of amount of Lightness but can change it’s Hue and Saturation, depending on which direction you go from the central elevator.

 

 

tumblr_ldms70QnbO1qz4zfrIn photography terms a color lives in a 3 dimensional space that can be accurately mapped and described by┬áit’s Hue, Saturation, and Lightness.

 

With this basic understanding of the 3 dimensional colour space, how can you then use it to describe a particular color when talking to someone, comparing one color to the next, or trying to change a color on your monitor while in Photoshop?

Communicating color with someone who doesn’t understand the language of color can be a challenge. We all use Hue to describe basic color. When you say to someone the color red, you’re referring to the term Hue, and they get a pretty quick mental picture of what that color is. But when you want to describe a darker red you need to figure out if you mean a red that has more Saturation and the same amount of Lightness, or are you saying that it needs to have less Lightness but keep the same amount of Saturation, or both? Understanding roughly where your original color is on the 3 dimensional space is useful in this case.

Evaluating a photograph using the 3d color model you can begin to mentally pick apart the various elements of Hue, Saturation, and Lightness (HSL) in each of the colors represented. When looking at a photo of a garden of red flowers for example, you can see the variations of red throughout the image. Depending on how the light falls on them, and whether they are the same type of flower or not, will change the values of Hue, Saturation, or the Lightness of each one. Armed with the right terminology you can now figure out the actual differences between them and either communicate this to someone, or be ready to decide how to make any color adjustments in your image processing software.

The mental process of evaluating color could go something like this. This red flower is different from that flower because it has more Lightness, is a Hue that is closer to Orange, but the Saturation appears to be about the same. Breaking a color into these three key elements is critical to communicating and understanding color in photography. In fact, Photoshop and other professional image editing software depends on you knowing this. Making changes to a photo without fully understanding what effect each of the controls and dialog boxes actually does to an image can be frustrating.

color_wheel_730So now you’ve opened an image in Photoshop, you’re looking at it and you want to change some of the colors. This is a topic for another blog coming soon, but color is actually one of the last things to consider when adjusting an image.

Firstly, has the image overall been exposed correctly, or is it too light or too dark overall? You have to answer this before you even start thinking whether the color is right or not.

Secondly, once exposure has been adjusted, the tonal range or gradation needs to be adjusted. This will be the topic for my next blog. Why tonal range and gradation before color adjustments?

As a photographer it is important that I am always aware of and monitor the color situation at each step of the process. The color decisions I make at the time I take a shot, process, or print an image all play an important role in the final outcome of each project.

I hope you find this information useful in your photography and when it comes time to communicating color you can speak to it using the Language of Color.

Carsten Arnold
carsten@carstenarnold.com