The V-Ray Ambient Light can be used to create light that doesn't come from a specific direction. It can be used to simulate GI, ambient occlusion, etc. It lights the entire scene evenly.

V-Ray Ambient Light is not supported by V-Ray GPU, yet.

UI Path:||V-Ray|| > Lights > Legacy Lights > Ambient Light

Enabled – Turns the light on and off.

Color – Determines the color of the light.

Intensity – A multiplier for the strength of the light.

Ambient Shade – Controls how the ambient light appears in the scene. A value of 0 shows light coming from all direction, while a value of 1 shows the light coming only from the direction of the light. A Texture can also be attached and blended with the Color using the Mix Strength parameter.

Affect Diffuse – Determines whether the light affects the diffuse properties of the materials.

Affect Specular – Determines whether the light affects the specular of the materials. This means glossy reflections.

Affect Atmospherics – Determines whether the light influences the atmospheric effects in the scene.

Diffuse Contribution – When Affect Diffuse is enabled, specifies a multiplier for the effect of the light on the diffuse component.

Specular Contribution – When Affect Specular is enabled, specifies a multiplier for the effect of the light on the specular component.

Atmospheric Contribution – When Affect Atmospherics is enabled, this value determines the amount of involvement.

Area Speculars – When enabled, the highlights match the shape of the light. When disabled, highlights are always calculated as if affected by a point light.

Cut-off Threshold – Specifies a threshold for the light intensity, below which the light is not computed. This can be useful in scenes with many lights, where you want to limit the effect of the lights to some distance around them. Larger values cut away more of the light; lower values make the light range larger. When this value is 0.0, the light is calculated for all surfaces.

Caustics Subdivs – Only used when calculating Caustics. Lower values mean more noisy results but render faster. Higher values produce smoother results but take more time.

Caustics Multiplier – This value is a multiplier for the generated caustics by the selected object. Note that this multiplier is cumulative - it does not override the multiplier in the Caustics render settings rollout section.

Project is used to create a list of objects that can be excluded (or included) from the light's effects.

Mode – Specifies whether the objects in the list are considered Included or Excluded from the light's effects.

Objects – Creates a list of objects to be excluded or included. When an object is added to the list, the  icons appear, which determine how the light affects the object. The  icon controls whether the emitted light affects the object. The  icon controls whether the shadows caused by the light affect the object. The  determines whether the object's children are affected.