1.1 Adaptive Dome Light & Auto Exposure and WB
V-Ray Next has a couple of new smart improvements that can greatly improve your workflow. With the data collected from the Light Cache prepass these features reduce both render setup and actual rendering time.
1.1.1 Adaptive Dome Light
First, let’s create a Sun and Sky system. Now create a V-Ray Dome Light and copy the Sky texture in it. Go to the dome light options and turn on adaptive dome light. Using this option we greatly speed up the render (up to 7 times). This option also removes the need of sky portals for interior rendering.
1.1.2 Auto Exposure and WB
Now let’s use another new feature to get the correct camera exposure. From the “Camera” rollout in the render settings, enable “Auto exposure”. We can also set the appropriate white balance by checking “Auto white balance”. Now we have proper lighting and the great thing is that we can focus on trying different light angles and different HDRIs without being distracted by camera settings or adjusting light intensity.
Note that the NVIDIA AI Denoiser is also enabled, almost instantly giving a really good idea of what the image is going to look like without noise during this look dev phase.
Once satisfied with the lighting you can transfer the automatically calculated exposure from the render settings of V-Ray to the Physical camera in the scene and uncheck the “Auto exposure” and “Auto white balance” boxes. Note that only the ISO parameter of the camera is going to be affected, preserving DOF and Motion blur settings.
For the final production render simply switch to the regular denoiser. Once you done this you might want to set the post effects rate to 0. Also you can increase the Light Cache subdivisions as they were reduced in this scene for the sake of interactivity.