Arnold fog is black

[pietarivisanti]

When I try to add fog to the scene, it's black. If I increase the distance and height, whole scene is more or less black. What could be the reason for that?

[pietarivisanti]

It should be noted that Fog (and Volume Fog right next to it) act as they promise. They come in to the material editor as black and render as black. Unfortunately if I change the colour to something else from white it still renders black. Maybe my computer is too weak or something and the fog refuses to work? I still managed to do everything else and be quite happy with the rest of the render, it just looks a bit flat without any fog in the horizon.

[ic198]

I'm having the same problem. I want to create a ground-hugging fog with buildings rising out of it. The fog seems to be the shape and density I want but it renders black. I have tried changing fog colour, lighting angle (this scene is using a sun positioner at midday), number of volume samples, colour of the underlying ground (in this image it's bright reflective white), height and start point of the fog- nothing I have tried seems to make a difference. Please can someone help?

[CiroCardoso3v]

I think Arnold's Fog doesn't like the Photometric Physical Sky

I used Arnold's Physical sky for this. File is attached

[ic198]

Thanks @CiroCardoso3v, changing to the Arnold Physical Sky fixed it for me. Is there any way to make a sun positioner control the Arnold sun? 

[CiroCardoso3v]

One way you can do this is by Parameter Wiring. Something like this

Let me know if you need a hand with this.

[ic198]

Thanks @CiroCardoso3v. I wanted to set this as an example for my students but parameter wiring is a bit beyond them at the moment- but it's good to know there is a way if I come back to it later.

[CiroCardoso3v]

Yeah, Arnold really needs to give us an Arnold Sun Light.