This page provides a step-by-step introduction to lighting an exterior nighttime scene in V-Ray for SketchUp.
In this tutorial we’ll go over lighting techniques for an evening architectural exterior scene using V-Ray’s Sun and Sky System.
To follow this tutorial, you will need to have the V-Ray for SketchUp plugin installed. This tutorial page is a companion that goes with the QuickStart video posted on our YouTube channel, and is available here:
To download the files used in this tutorial, please click on the button below.
Open the Example Scene
Begin by launching SketchUp. Open the project file QS_Day_for_night.skp, which can be downloaded from the Tutorial Assets section above. The scene comes set up with a Sun & Sky system, and a camera exposed for daytime.
Start an Interactive Render by clicking on the Render Interactive button on V-Ray's Toolbar.
The V-Ray Frame Buffer (VFB) opens up and starts rendering the initial daytime image interactively. Almost all subsequent changes will force the render to restart, updating the new settings and displaying the changes accordingly. Keep in mind that some parameters still require a manual restart in order to update properly.
Darkening the Image
The first thing to do to darken the image is to move the position of the Sun below the horizon. Navigate to the Shadows rollout in SketchUp's tray and change the Time to 17:30 (making sure the rest of the settings are also in line with the parameters below).
The VFB will update the settings immediately, rendering a much darker version of the exterior.
Next, we need to make changes the Sky. Open the V-Ray Asset Editor from V-Ray's Toolbar.
Go to the Settings tab and expand the Environment rollout. Disable Aerial Perspective so as to see the Sky more clearly.
The V-Ray Sky will not be needed for the purpose of this tutorial so you can go ahead and remove it by right-clicking on the checkered icon and selecting Clear.
Now we need to assign a new environment background. Left-click on the color rectangle next to Background and choose a solid blue colour from the dialog that appears.
Wait for the VFB to update the image:
As you can tell, the image is now way too dark. We can fix this by adjusting the camera Exposure Value (EV). Expose the Camera options and change the EV to 9.
Observe the VFB:
The render now looks much better and brighter but there is more we can do improve it. Turn Aerial Perspective back On and adjust the Visibility Range (m) to 11 000. Then copy the blue Background color and paste it into the Filter color.
Let the VFB update the image:
The render now looks like a moonless night. All we need to do now is light up the interior and exterior of the building.
Setting up the lights
Next, we are going to turn on some of the artificial lights. Navigate to the Lights tab in the V-Ray Asset Editor and turn both V-Ray Rectangle Light and V-Ray Sphere Light on by left-clicking on the icons next to their names. The Rectangle Light lights up the exterior while the Sphere Light - the interior. The lights are adjusted to fit the purpose of the scene but you are free to experiment with their parameters for a different look that suits you best. To expand the individual properties of the lights, left-click the arrow on the right-hand side of the V-Ray Asset Editor.
The VFB updates:
We have successfully lit up our nighttime scene.
Post-Production and Final Render
The render now looks quite well but there is even more we can do to boost the photorealism of the final image.
Stop the Interactive Render by clicking on the Stop button within the VFB. Then click on the Open lens effects settings at the bottom to expand the lens effects menu of the VFB.
Turn Bloom and Glare on. By default the lens effects are applied to the whole image, however, in this example we only need them applied to the light sources. This can be done through an intensity mask which creates a mask of the brightest part of the image, in this case - the lights inside of the building. The lens effects will then be applied only to the masked areas. Turn on the Bloom and Glare Intensity Masks.
The final image is now ready for production rendering. Open the Settings tab within the V-Ray Asset Editor, expand the Renderer rollout and disable both Interactive and Progressive.
Click the Render button on the V-Ray Toolbar.
Wait for the render to finish. You can tweak the values of the lens effects further, as well as apply color corrections, to get the final look that suits you best.