There are many different light types to choose from in your 3D application of choice and knowing which one works best for your scene is key to creating a great render. Let's go over the prominent light types that you will be using most so you can learn what lighting will work best for your next project.
A spot light behaves exactly how it sounds, like a real spot light, and provides a very direct source of light. One of the key benefits that you get when using a spot light is the directionally that you get from the light. The spot light is emitted through a cone and you can control how wide the cone angle is which determines how much of the area is actually illuminated. Objects closer to the spot light will be brighter, and depending on the how wide the cone is the light will either be softer or harder.
With the editability that a spot light provides, you can create very unique light illumination, like light coming through a crack in a door or the conical light shape that a flash light provides. A common use for a spot light is to create three point lighting, which utilizes three spot lights to create very unique studio lighting effects.
Maya and CINEMA 4D refer to these light types as Spot Lights, but in 3ds Max they are called a Free Spotlight, or a Target Spotlight. The main difference between the Target Spotlight and the Free Spotlight is that the Target Spotlight has an aim constraint attached to it, so you can focus light on an object easier. Softimage simply calls these lights a Spot. Even though different 3D applications call them different things, the functionality is essentially the same.
Point lights are the most common light types found in 3D software. A point light is very similar to an incandescent light bulb that emits light in all directions. You can think of a point light as a sphere of light filling an area. Objects closer to the light will be brighter, and objects further away will be darker.
Point lights are great when you need to illuminate areas with a smooth falloff in all directions, or create a light that has a single point as its source, like a lamp or candle.
Each 3D application calls a point light something different, but the purpose and end result is the same. Maya refers to these lights as Point Lights, where 3ds Max calls them Omni Lights. Softimage just calls them Point, and CINEMA 4D simply calls them Light.
An area light is a light that casts directional light rays from within a set boundary, either a rectangle or circle. This type of light is perfect for recreating florescent lights or something that is rectangular.
For example, light shining through a window, or florescent ceiling lighting. All other light types emit light from a single point, where an area light emits light from an entire area which is generally more realistic. This type of light does have a cost when it comes to render time, because the computer needs to process all these extra light points.
CINEMA 4D and Maya both refers to these light types as Area Lights. Softimage refers to them as a Light Box. 3ds Max calls them mr Area Spotlight.
A directional light mimics the lighting that you would get from the sun. Directional lights emit parallel light rays in a single direction but the light reaches out into infinity. You can think of a directional light as a giant flash light very far away from your objects, always centered and it never dies off. You can rotate the light in any direction. Because a directional light represents a distant light source like the sun, its X, Y, and Z coordinates mean nothing, only its rotation values.
This type of light is perfect when needing to illuminate a city or large open spaces.
In 3ds Max these light types are referred to as either Free Directional Lights, or Target Directional Lights the only difference being that the target directional light uses a target object to aim the light. Both Softimage and CINEMA 4D call them Infinite Lights. Maya calls them Directional Lights.
A volume light is very similar to a point light, emitted omni-directional rays from a single point. Unlike a point light though, a volume light has a specific shape and size, which affect its falloff. A volume light can be changed to any geometric primitive: a cube, sphere, cylinder or cone. The volume light only illuminates objects within its volume. Meaning if you want the object to be lit up, the volume light will need to be placed around the object.
Maya is the only 3D application that has a light option called a Volume Light that creates a volumetric light. Most other 3D applications do this through different light settings for any given light type. The most common use for this type of light is to create volumetric light patterns which is used to show beams of light shining through the environment, like fog, or streaming through an open window.
An ambient light casts soft light rays in every direction. It has no specific directionality so does not cast any shadows or shading, and simulates more of a secondary light that is coming from all different angles and is applied to all objects in a scene. Ambient lighting is great for filling in areas on a render that do not have enough illumination.
Ambient light is also great for creating cartoony like light effects for your scene, depending on your light settings.
Maya refers to this effect as an Ambient Light, and in Softimage it is called a Flat Light.
Experiment with these different light types in your 3D application to see the effects that it has on your scene. It’s best to use different light types in conjunction; it is very rare that you will be able to get the job done with just one single light.
Keep learning with more 3D lighting posts and 3D lighting tutorials.