Image based lighting using HDRI maps is a popular choice for creating studio type environments in V-Ray. However if attempting the popular white studio with a reflective floor and soft shadows, the HDRI ends up being reflected in the floor as well as the scene objects. This tutorial will explain how to remove the HDRI reflection in the floor but keep the reflection and illumination for the scene objects in V-Ray.
Create a V-Ray plane and apply a V-Ray material to it. In the material, set the reflection up to how you want it, either a blurred glossy finish or a pin sharp reflection. You may also wish to disable Fresnel in order to generate a stronger reflection. The diffuse colour will affect the illumination on the scene objects so set this to a mid grey or close to black.
Right click the V-Ray plane and go to V-Ray properties. Tick matte object and matte for reflection/refraction. Set alpha contribution to -1 and tick both shadows and affect alpha. The plane will now only catch shadow and reflection, it will not show up as a diffuse material.
In the environment settings change the background colour to pure white.
When you are setting up your render settings in the V-Ray colour mapping, untick affect background. This will make V-Ray render a pure white background and floor (as there is no diffuse for the floor) regardless of the exposure settings.
Create a V-Ray dome light and add an HDRI as a texture. Call this light HDRI reflection. Untick affect diffuse and tick invisible.
In the exclude options, exclude the V-Ray plane. Make a copy of the dome light and call it HDRI diffuse. Tick affect diffuse to enable it and untick affect specular and affect reflections. In the exclude list remove the V-Ray plane from the list.
You will now have one dome light that creates reflections only on the scene objects but excludes the ground plane and the other dome light only affects diffuse of both the scene objects and the ground plane to generate shadow.