![[VrayLight_Sun]](images/VrayLight_Sun.jpg)
Physical Sun - turns on and off the sun light.
Sun invisible - when on, this option makes the sun invisible, both to the camera and to reflections. This is useful to prevent bright speckles on glossy surfaces where a ray with low probability hits the extremely bright sun disk.
Physical Sky - turns on and off the sky light and environment.
Sky intensity multiplier - this is an intensity multiplier for the Physical Sky. The multiplier can be set to greater than 100%. Note that Physical Sky intensity increasing does not affect Physical Sun brightness intensity.
Override Background Env - when this option is unchecked Physical Sky has no effect to Background and Background from Enviroment tab will be visible on render.
Override GI Env - when this option is unchecked Physical Sky has no effect to GI Enviroment and GI Enviroment from Enviroment tab will be visible on render.
Override Reflection Env - when this option is unchecked Physical Sky has no effect to Reflection and Reflection from Enviroment tab will be visible on render.
Override Refraction Env - when this option is unchecked Physical Sky has no effect to Refraction and Refraction from Enviroment tab will be visible on render.
Turbidity - this parameter 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 further info, please see the Examples section.
Ozone - this parameter 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 further info, please see the Examples section.
Water vapour - aqueous vapor, is the gas phase of water. Water vapor is one state of the water cycle within the hydrosphere. Not used in current version.
Intensity multiplier for Phys Cam - this is an intensity multiplier for the Physical Sun. Since the sun is very bright by default, you can use this parameter to reduce its effect. See the Notes and Examples sections for more information.
Intensity multiplier for Std Cam - this is an intensity multiplier for the Physical Sun. Since the sun is very bright by default, you can use this parameter to reduce its effect. This multiplier affects only on Cinema4D Camera render, even if it have VRay Physical Camera Tag on it.
Size Multiplier - this parameter 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 further information, please see the Examples section.
Photon emit radius - determines the radius of the area, in where photons would be shot.
Photon emit distance - determines the distance of the area, in where photons would be shot. This area is represented by the green cyllinder around the Sun's ray vector. This parameter has effect when photons are used in the GI solutions or caustics.
Notes
- By default, the VRaySun and VRaySky are very bright. In the real world, the average solar irradiance is about 1000 W/m^2. Since the image output in VRAYforC4D is in W/m^2/sr, you will typically find that the average RGB values produces by the sun and the sky are about 200.0-300.0 units. This is quite correct from a physical point of view, but is not enough for a nice image. You can either use Color mapping to bring these values to a smaller range (which is the preferred way) or you can use the Sun intensity multiplier to make the sun less bright. Using the VRayPhysicalCamera with suitable values also produces a correct result without changing the sun and sky parameters.