Relationship between dome light .exr / .hdr image and exposure

[bryan_sears]

I am having trouble keeping detail in my dome light image (as a sky) while illuminating the scene. As I understand the method, I should only use either a dome light or the sun to illuminate a scene— maybe this is not the way. I've experimented with the advanced camera settings, the rotation of the bitmap image in the dome, the intensity, different .exr, and my results are a blown out sky if I want to illuminate an exterior scene. Has anyone got any advice? I've also tried various .exr / hdrs, looking for one that isn't a sunset of course, something with a good overall light and sky details. I'm using assets from Vizpark, primarily. I've also noticed that the preview in the mirror ball is almost never what is shown in the render, so I've probably got something to learn.
Thank you for your help.

[konstantin_chaos]

Hi bryan_sears,

There are numerous ways to setup exterior lighting in V-Ray.

Sun & Sky
By default all V-Ray for SketchUp scenes are setup in this way.
It works great in many situations but the sky is always clear - there are no clouds and other details visible.
Note that the Sky texture is by default connected to the V-Ray environment but you also have the option to connect it to a Dome Light.
This would give you much better results in interiors.

Dole light with a sky texture
This method involves the creation of a Dome Light in the scene and the use of a HDR image of your choice.
The HDR images available online vary in their intensity quite a bit so chances are you'll have to account for that with the Intensity parameter of the Dome light source.
Note that if there is a visible sun disk (bright spot) in the HDR image you can just disable the Sun light source in the scene.
If there is no visible sun in the image, you can keep the Sun light - it'll shine through the Dome but will not appear in the Sky.

Using Light Gen
A really straight forward way for you to setup an exterior scene in V-Ray 5 is with Light Gen.
You can read more about this tool here - Light Gen
It can setup your scene using either Sun and Sky or a HDR image.
The cool thing about it is all the built-in HDRs are balanced to match natural daytime light intensity.

Regards,
Konstantin