--- title: "V-Ray Sky" canonical: "https://documentation.chaos.com/space/VRAYHOUDINI/113279444/V-Ray%20Sky" format: markdown --- This page includes details about the Sky texture used for the environment within the V-Ray Sun and Sky System . Overview 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 Light , which is normally used in conjunction with the V-Ray Sun and Sky System . The example below on the left is a swatch of the sky map with a visible horizon line and ground. The renders to the right show a chrome shader ball and a diffuse shader ball with the V-Ray Sky texture map as an environment along with sun lighting. Parameters Find Sun Automatically  – When enabled, attaches the  sun  automatically and takes settings from it. Sun  – Creates a connection between a  VRaySun  and the  VRaySky  object to calculate its appearance. Overwrite Sun Settings  – Overwrites the  VRaySun  Settings that would otherwise be taken from the Sun node. This is useful when using the  VRaySky  without a Sun node. Sky Settings Invisible  – Controls whether the shape of the Dome Light source is visible in the resulting render. When disabled, the source light is rendered in the current light color, otherwise the light source itself is not visible in the scene. Note : This parameter only affects the visibility of the light when seen directly by the camera or through refractions. The visibility of the light with respect to reflections is controlled by the  Affect Specular  and  Affect Reflections  options. Sky Model  – Determines the procedural model that is used to generate the V-Ray Sky texture: Preetham et al.  – When selected, the  V-Ray Sky procedural texture is generated based on the Preetham et al. method.  CIE Clear  – When selected, the V-Ray Sky procedural texture is generated based on the CIE method for clear sky. CIE Overcast  – When selected, the V-Ray Sky procedural texture is generated based on the CIE method for cloudy sky. Hosek et al  – When selected, the V-Ray Sky procedural texture is 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. PRG Improved – The V-RaySky procedural texture is generated using the improved PRG Clear Sky method. The updated PRG Improved allows for rendering the sky at various observer altitudes, up to several kilometers. It also supports rendering of nautical twilight effects with sun positions up to 12 degrees below the horizon. Additionally, it features enhanced turbidity control, enabling the rendering of sky conditions with turbidity values ranging from 1.81 to 4.89. S ee the Sky Model Types example below for more information. Intensity Multiplier  – Determines the intensity value when overwriting the sun settings.  For more information, see the Intensity Multiplier example on the  V-Ray Sun Light  page. 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.  For more information, see the Size Multiplier example on the  V-Ray Sun Light  page. 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.  For more information, see the PRG Improved - Turbidity example below and the Turbidity example on the V-Ray Sun Light  page. Ozone  – Affects the color of the sun light. Available in the range between  0.0  and  1.0 . Smaller values make the sunlight more yellow, larger values make it blue.  For more information, see the Ozone example on the  V-Ray Sun Light  page. Water Vapour  – Controls the amount of water vapor in the atmosphere which affects the sky color. Color  –  Shifts the hue of the V-Ray Sun and Sky system towards the color specified in the field. 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 towards 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. Ground Albedo  – Sets the ground color of the V-Ray Sun and Sky system. Horiz. Surface 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. Horizon Offset – Offsets the horizon from the default position (the absolute horizon). Blend Angle – Controls the size of the gradient formed by V-Ray Sky between the horizon and the actual sky. Altitude – Controls the observer's altitude in meters. As the altitude increases, sky clarity improves, and the horizon line becomes less defined. For more information, see the PRG Improved - Altitude example below. Example: Sky Model Types The examples below show the different sky model types. Here, default values for V-Ray Sky have been used. Preetham et al. CIE Clear CIE Overcast Hosek et al. PRG Clear Sky PRG Improved Example: PRG Improved - Turbidity In this example, you can see how the amount of dust in the air affects the color of the sun and sky. Smaller values produce a clear image, while higher values dim the sun and sky.  Turbidity = 2 Turbidity = 2.6 Turbidity = 3 Turbidity = 4 Turbidity = 5 Example: PRG Improved - Altitude This example shows how the Altitude values affect the visualization of the sky. Higher Altitude values result in better sky clarity and a less defined horizon line. Altitude = 0 Altitude = 1000 Altitude = 2000 Altitude = 10000 Altitude = 15000