CHAPTER 10
Adding Color And Light

Featuring

•  Understanding Color Models

•  Creating and Positioning MAX Lights

•  Using the Light Lister

•  Using the Color Clipboard

•  Setting Light and Shadow Parameters

•  Applying the Knowledge of the Masters

•  Designing Your Lighting

This chapter will discuss the use of color and lighting and their implications in the final render of your MAX scene. We will cover the features of MAX lights and related tools. You will learn how to use the various settings for each type of light. Finally, this chapter will cover different approaches to setting up the lights of your scene.

Lighting can be very subjective. Not only do no two people light a scene exactly the same way, but also no two people will see the same result. Our physical sight, which may seem to us such a given—an impersonal input from the world to our eyes and our brains—is in fact something that must be trained to make fine distinctions. While few people who see your final rendered product will be able to make those fine distinctions consciously, all of your audience will be (at least subconsciously) affected by the slight differences in light and shadow that create very different moods and meanings.

Moods and meanings? That sounds more touchy-feely than technical; how can you train yourself in this area? The nuances of interplay between lighting and meaning has been studied intensively since films were first made. The meaning of a certain lighting style can never be absolute, since it depends on cultural conventions and precedents for its validity; yet using it can make the difference between effectively conveying your story and leaving your audience yawning.

Lighting is a complex study that takes years of experience to master. In film, teams of people specialize in perfecting just the lighting of scenes. If you are working on your own animation without the luxury of a team of specialists, you have to be your own lighting crew, in addition to being your own writer, director, camera operator, model builder, animator, and editor. It’s a challenge to learn all these aspects of filmmaking at once. Any experience you acquire in real-world lighting for photography, film, or video will help you in lighting your virtual set in MAX. You can also watch movies with an eye for lighting effects, the mood these create, and how they might be produced digitally.

Understanding Color Models

Whether we use colored lights or special materials, we are coloring the pixels of our rendering and so are interested in the dramatic and intriguing effects color can create for the eye. Knowing how we see color can help us choose our colors effectively. Color is understood according to various models (also called color spaces) invented to describe them. Not all colors that occur in nature are described by any model, nor do the models perfectly translate to each other.

The Subtractive Model

We see color on surfaces because pigments absorb and reflect parts of the spectrum of light. Our eye picks up the light that is reflected and sends this info to the brain for interpretation. Pigments fit a color model based on the subtractive primary colors: cyan, magenta, and yellow. This model is called subtractive because as new pigment is added, the color that pigment reflects is being subtracted from the light we see reflected. When all light has been subtracted, we are, in theory, left with black. In practice, it is difficult to get a true black by mixing cyan, magenta, and yellow pigments, so black is added. This is the CMYK system (K is short for black) used for print.

The traditional color wheel taught to us since grade school is subtractive in nature, and much of our real-world experience with color involves mixing pigments, so this model is more intuitive to most of us than the additive models. Since we are referring mainly to the output of our computer monitors in this book, however, we will stick to the additive models.

The Additive Models

All light-based transmissions (such as computer monitors, film projections, TV screens, or colored filters on flashlights) fit the RGB color model, based on the additive primary colors: red, green, and blue. This model matches the system used by the red, green, and blue cones in your eye that pick up all the color information you see.

The additive colors of light combine to create white light. In the RGB model, red and green produce yellow, which can seem counter-intuitive; red and blue produce magenta; and green and blue produce cyan. This gives us a wheel with the three primaries of light and their complements. If you open additive_wheel.jpg on the CD, you can see an example of this wheel. Notice the complementary pairs across the wheel from each other: red and cyan; green and magenta: and blue and yellow.

In the RGB model, an image is defined solely by the red, green, and blue values of each pixel. You can specify exactly what color you want by entering its RGB values into the Color Selector dialog box (Figure 10.1) brought up by any color swatch in the Material Editor.

FIGURE 10.1  Color Selector dialog box with RGB, HSV, and HWB options

The HSV Model

The hue, saturation, and value (HSV) model, sometimes called hue, lightness, and saturation (HLS), still works with the additive system of the RGB model, but is viewed in a different format. A color in this system is defined by its hue, which is the specific color along the spectrum; its saturation, which is the purity or intensity of the color; and its value, which is the grayscale lightness or darkness of the color. You can specify an exact color by entering these values in the Color Selector shown in Figure 10.1.

The HWB Model

A color model related to the HSV model is the hue, whiteness, and blackness (HWB) model. It is based on a system more familiar to painters, where a color is defined by its hue, the amount of white added, and the amount of black added. It can also be used in the Color Selector interface (Figure 10.1), by adjusting the sliders around the large color plot.

It doesn’t matter which of the Color Selector models you use to choose your colors. One will probably make more sense to you intuitively, so use that one. You can also get part of the way there with a slider in one model and then adjust it with a slider in another. For example, you might click directly on a color that is close to what you want in the HWB section of the Color Selector, and then turn down the saturation slider in the HSV section.

Exploring the Color and Light Tools in MAX

In addition to understanding the real-world effects you want to imitate, you also need to understand the special characteristics of computer graphics (CG) lights that differ from real lights, so that you know how to adapt your strategy. Let’s look at the color and lighting tools available in MAX.

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