Lighting shapes the way we see the world. In both real and fictional spaces, we use lighting to set the mood and direct attention. Photographers, cinematographers, filmmakers, and 3D artists must be experts at using lighting effects to either reproduce reality or stylize a scene.
3D Lighting: Types of Lighting and 3D Lighting Techniques
Five types of 3D light sources.
Whether you’re just getting started with basic lighting techniques or you’re working on sophisticated arrangements, you must first understand the sources of light you can use when creating a lighting setup.
- Directional light: This source of light emits parallel rays that wash an object as if the source is a distant one — like the sun. It strikes every element in a scene with equal intensity.
- Area light: This light source is defined by a rectangle with directional rays emerging from a specific surface. This sort of light resembles the light that would pass through a window, or to replicate a studio softbox, and creates highlights of specific shapes.
- Point light: A point light is a source that sends out light in all directions. Point lights can be used to simulate the light emitted by a lamp or incandescent bulb.
- Spot light: While a point light resembles the light from a table lamp, a spot light is more like a flashlight. The light shining from a spot is constrained by a certain angle. The intensity of the light diminishes the farther an object is from the source as well as diminishing along the edges of the cone of light.
- Sky dome lighting: With this lighting choice, light washes down on the scene from overhead. It is mostly used for outdoor scenes to re-create the effect of the ambient lighting from a bright sky.
One-, two-, and three-point lighting examples.
In addition to the different types of light, the number of sources you use will define the character of the 3D environment.
This approach to lighting uses a primary source, or key light, and then a secondary source. The key light will be the stronger light. The second light can be used to fine-tune the contrast or separate the subject from the background.
This is a common lighting choice in 3D renderings, coming from the cinematographic Hollywood lighting style. It consists of three different light sources. The key light will be the main source of light for your subject. The fill light will help control the contrast by attenuating the shadows from the key light. The backlight, or rim light, will be a strong light placed behind the subject to help separate it from the background.
Four tips for creating realistic 3D lighting.
Study the real world.
3D lighting is an art and, like many art forms, becoming a master of it can begin with observation. Study how lighting changes during the course of the day, the mix of natural and artificial sources that light your world, and how moving the light sources in a room can change its feel.
Keep it simple.
With an outdoor daytime 3D scene in particular, one or two light sources are often sufficient. In real life, the sun typically provides most of the light, so a sky dome can be used to simulate the play of light and shadows common in outdoor scenes. There is often no need for point, spot, or other light sources.
Cinematographers are masters in lighting design. Beginners can learn a lot by watching movies acclaimed for their cinematic techniques.
Play with implied lighting.
By lighting scenes with undefined sources just beyond the frame of your image, it’s possible to create an image that is at once both more mysterious and truer to life. The world will not appear to end at the edges of your composition.
Consider color too.
While the direction and nature of the light source will be your primary focus, consider the quality of the light as well. Different types of light — pure white, bluish, and yellow light, for example — will result in very different moods.