Use Point Lights (Concept)

Point Lights

A point light radiates light in all directions from its location. A point light does not target an object. Use point lights for general lighting effects. You can create a point light by entering the POINTLIGHT command or by selecting a point light from the Lights panel on the ribbon.

You create a target point light with the TARGETPOINT command. The difference between the target point light and a point light is the additional target properties that are available. A target light can be pointed to an object. A target point light can also be created from a point light by changing the target property of the point light from No to Yes.

In the standard lighting workflow, you can set a point light manually so its intensity diminishes with respect to distance either linearly, according to the inverse square of the distance, or not at all. By default, the attenuation is set to None.

Point Lights in Photometric Workflow

A free point light can have photometric distribution properties. The attenuation for a photometric point light is always set to inverse square.

When the LIGHTINGUNITS system variable is set to 1 (International SI units) or 2 (American units) for photometric lighting, additional properties are available for a point light. On the Properties palette, photometric properties are

Lamp Intensity. Specifies the inherent brightness of the light. Specifies the intensity, flux or illuminance of the lamp.
Resulting Intensity. Gives the final brightness of the light. (Product of lamp intensity and intensity factor. Read-only.)
Lamp Color. Specifies the inherent color of the light in Kelvin temperature or standard.
Resulting Color. Gives the final color of the light. This is determined by a combination of the lamp color and the filter color. (Product of lamp color and filter color. Read-only.)

NoteWhen the drawing lighting units are photometric, the attenuation type property becomes disabled. Photometric lights have fixed, inverse-square attenuation.

The additional information about these properties are available under Lighting Properties. The following image is an example of a photometric point light and lighting properties palette with the photometric properties outlined: