Sky

The V-Ray Sky texture map is typically used as an environment map to help simulate outdoor lighting. The texture changes its appearance based on the position of the V-Ray Sun, which is normally used in conjunction with the V-Ray Sun and Sky System. The example is a swatch of the sky map with a visible horizon line and ground.

UI Path: ||V-Ray Node Editor|| > Shader > Add > Textures > V-Ray Sky

Filter Color – Shifts the hue of the V-Ray Sun and Sky system toward the color/node specified in the field.

Ground Albedo – Sets the color of the V-Ray Sun and Sky system's ground.

Intensity Multiplier – Determines the intensity value when overwriting the sun settings.

Turbidity – Determines the amount of dust in the air and affects the color of the sun and sky. Smaller values produce a clear and blue sky and sun as you get in the country, while larger values make them yellow and orange as, for example, in a big city. This parameter is not available for the PRG Clear Sky Model.

Ozone – Affects the color of the sunlight. Available in the range between 0.0 and 1.0. Smaller values make the sunlight more yellow, larger values make it blue. This parameter is not available for the PRG Clear Sky Model.

Size Multiplier – Controls the visible size of the sun. This affects the appearance of the sun disc as seen by the camera and reflections, as well as the blurriness of the sun shadows. 

Sky Model – Determines the procedural model that will be used to generate the VRaySky texture:

Preetham et al. – When selected, the  VRaySky procedural texture will be generated based on the Preetham et al. method. 
CIE Clear – When selected, the VRaySky procedural texture will be generated based on the CIE method for clear sky.
CIE Overcast – When selected, the VRaySky procedural texture will be generated based on the CIE method for a cloudy sky.
Hosek et al – When selected, the VRaySky procedural texture will be generated based on the Hosek et al. method and uses a different ground and sky gradient.
PRG Clear Sky – The V-Ray Sky procedural texture is generated based on the PRG Clear Sky method which has enhanced sunrise and sunset sky.

Horiz Illum – Specifies the intensity (in lx) of the illumination on horizontal surfaces coming from the sky. Note: Only available when CIE Overcast or CIE Clear are selected as the Sky model.

Color Mode – Specifies how the Filter Color affects the color of the Sun:

Filter – Shifts the hue of the V-Ray Sun and Sky system toward the color specified in the Filter Color field. 
Direct – Sets the color of the V-Ray Sun to match the color in the Filter Color parameter. In this case the intensity of the light does not depend on the V-Ray Sun's position in the sky and is controlled through the intensity multiplier. 
Override – Sets the color of the V-Ray Sun to match the color in the Filter Color parameter but the intensity of the light still depends on the V-Ray Sun's position in the sky.

Filter Color – Shifts the hue of the V-Ray Sun and Sky system toward the color specified in the field. Allows a node to be connected, as well.

Blend Angle – Specifies the angle in degrees where blending will occur between the horizon line and sky. Values close to 0.0 produce a sharper horizon line, while larger values produce a softer horizon line.

Horizon Offset – Allows the user to manually lower the horizon line.

Water Vapour – Controls the amount of water vapor in the atmosphere which affects the sky color.

Invisible – When enabled, the connected V-Ray Sun becomes invisible to both the camera and to reflections. This option is inactive when no V-Ray Sun is attached.

Sun – Attach the V-Ray Sun Light in the scene to this slot to automatically take settings from it.

Sun Direction Only – When enabled, uses only the direction of the specified sun. No other parameters will be inherited. This option is inactive when no V-Ray Sun is attached.