What approach is the right or best one for using IBL (HDRI)

[mitthrawnuruodo]

I have two HDRI versions

- low res blurry HDRI for diffuse lighting

- high res sharp HDRI for reflections and specs

 

First solution

Blurry HDRI in my dome light, aligned with sun (for better shadows),

Sharp HDRI in my Environment slot

 

Then I have to make dome light invisible to render so that sharp background is being rendered, but the reflections are still blurry, I could also uncheck reflection and spec tick box on the Dome light (I am not sure if this is the way to go).

 

Second solution

I could just use vray's environment switcher rollout in render settings, and after properly aligning sun position with the Dome HDRI just turn this light off and leave it to the switcher.

 

Third solution

Just use the sharp HDRI for everything.

 

So again what is the right way to go OR the best way to go?

[RyderSK]

What you're refering is called smartIBL(/sIBL) and is a general concept for lighting in CGI irrespective of renderer choice. But different renderers integrate sIBL is some form or another directly so you don't need to do this setup manually. Vray does downsample the image for sampling (it's the resolution factor of DomeLight, by default 512px) of light and uses full resolution for reflection. I would suggest keeping this solution.

 

You can additionally make the DomeLight invisible and use the switcher to get Alpha Channel (this is workaround isn't necessary in Vray3.0 anymore), if you want so, make the DomeLight intensity 1.0 so it matches the texture.

[mitthrawnuruodo]

Thanks very much for clarifying this to me Juraj.

[Stephen Thomas]

It's worth using the sIBL loader script from HDRLabs.com This does all the hard work for you, as well as setting up rotational links between maps that you can control easily by a visible sphere in your viewport and also gives you the option to attach a direct light source.

[mitthrawnuruodo]

I am going to try that script, I did see it but never used it yet. But as Juraj said it is kind of pointless in vray as it does it all for you. Will try it anyway to see how it goes