Dome Light & HDRI Reflections

[Claudio Branch]

I am using a V-Ray dome light with an HDRI image and a direct light on an exterior scene.

 

I have a building with some windows that I want to reflect the HDRI. I put a raytrace material in the reflection slot and the glass is picking up the surrounding structure of the building, but not the HDRI image.

 

Any suggestions?

[Ricardo Eloy]

First, no raytraced materials with VRay, pal. They are not meant to each other. Use a VRay Material instead. That said, using a VRayMat will automatically give you the reflections you're looking for.

[Stephen Thomas]

Yeah, don't use raytrace with Vray. Instead copy the HDRI map to your environment slot. Generally I would use two versions of your HDR. One small blurred version for your lighting and one larger version in the reflection override slot. You can then control the intensity of these independently, and the blurred HDR will give you a smoother GI solution.

[vansteePieter]

mm that's interesting

 

cause I've also having some problems with hdri and reflections...

When I render my scene, mostly with a modern house, up till now, I'm having difficulties to show the HDRI reflection on the windows.

I'll explain how my settings are, maybe you can help me out...

 

First of all I use a daylight system, with vray sun and shadows etc.

then I add an hdri to the environment slot but nothing appears untill I increase the hdri multiplier (in the mat editor itself) to upto 300x or more

 

so is there something I did wrong?

should I post some screenshots of my settings

 

kind regards Pieter

[Ricardo Eloy]

I guess this depends on the HDRi you're using, Pieter. Some maps are really dark (we've created a couple that demand a very high multiplier in order to be seen, too).

[Joseph Petrino]

Just to add my perhaps worthless 2 cents:

 

You did mention a dome light.

 

In my scenes HDRI stops working when I use a Vray Dome light. Any other light (vray or whatever) is ok.

[Stephen Thomas]

Sorry, haven't used the dome light much recently. Should have said that if using the dome light with HDRI then you don't need to use the environment slot as the image automatically becomes your background. So leave your environment swatches at black.

 

Just one other thing to check, you are using the VrayHDRI map in your dome light and not just importing your HDR as a bitmap aren't you?

[Ricardo Eloy]

I simply did not read "dome light"... It must be the age. Anyway, if you are not using the HDRI in your dome light, turn the "invisible" option on. A dome light, as mentioned, becomes your BG unless you tell it not to.

Another tip: when using a HDRI for lighting, it's best used if inside the dome light instead of the environment slot. The light and shadows come out much sharper and precise.

[Claudio Branch]

I have the HDRI reflecting off of the windows now. I changed the window material to VRayMtl and used the color swatch to control the amount of reflectivity.

 

I also discovered that the VRayLight multipler (in the light rollout) has no effect on the amount of light it is generating. It is apparently controlled by the multiplier in the instanced VRayHDRI in the Material Editor instead.

 

How do I control the scale of the HDR image in the backgound? It is huge.