U g I n f o r d e s I g n e r s

V-Ray for SketchUp
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Adding the V-Ray Sky
In V-Ray for SkechUp the Sky is added in the environment rollout of 
the V-Ray options, click on the "m" next to GI parameters. You must 
have Indirect Illumination enabled to access this, so enable it if you 
have not already. Clicking the "m" should bring up the texture editor, 
and under Type select Sky. At the top you will notice the option to 
select a light source, the SketchUp sun is selected by default and V-
Ray knows where the sun direction is coming from. Lastly, there is an 
option next to the button that says Override Sun's Parameters. This 
allows separate settings for the Sun and the Sky, but for simplicity and 
continuity it is recommended to have this unchecked. Now go ahead 
and repeat this process for the background. If we render again we'll 
notice that our white ground plane has a slightly blue hue to it. This 
is due to the influence of the sky on our scene.
Time of Day and the Sun’s appearance
Now that we have added the sun and sky, let’s see how the sun reacts to changing the time of day. In 
order to change the position of the sun, simply adjust the time of year and day using SketchUp Shadow 
Settings. (You can adjust the location through SketchUp Model info). Now the appearance of the scene 
has completely changed sole based on the position of our sun. This allows users the flexibility to worry 
only about the time of day rather than adjusting the appearance and intensity of the sun and the 
background.
Changing the Sun’s Appearance with Turbidity
Although the time and position of the sun will have the most affect on the appearance of the Sun and Sky, 
there are several other controls that will be helpful in adjusting their appearance. Turbidity essentially 
changes the amount of dust that is in the air. Values on the lower end or the spectrum will create a very 
clear blue sky as you would see in the country side. Having larger values will make the sky slightly 
yellow or orangish as you would see in the city. Think of turbidity almost as a control for the haziness of 
the sky.
Morning
Mid-Day
Evening
Turbidity= 2, Clear Day
Turbidity= 5, Slightly Hazy 
Turbidity= 8, Very Hazy Day