Volume light

[Devin Johnston]

What's the best way to do volume lighting in an animation, I've tried using standard lights before but got some strange results. I've tried using environment fog but I don't think there's a way to confine the fog to just the light. Any help will be appreciated.

[Nicolai Bongard]

If you are using vray, you can define a shape/volume to contain the fog (a helper or a mesh object), and you can specify the light sources you want to affect the fog. If you go to peter guthrie`s blog, there is a tutorial for how to set it up. I have not yet tried to use fog in an animation, so i cannot vouch for how well it works, but in stills the vray fog looks really nice.

[Devin Johnston]

Nicolai I've looked for that tutorial and can't find it. From my experience with vray environment fog you have to use an atmospheric gizmo to constraint the fog but this doesn't really work if you want to limit the fog to only the light beam.

[Corey Beaulieu]

Devin, what were the strange results on the standard light methods?

 

I would and have in the past just rendered this as a separate pass by hiding all glass objects and overriding the entire scene with a black material. You can then comp this pretty easily in post.

[Devin Johnston]

The lights would flicker and change color.

[RyderSK]

I would avoid gizmos (peter uses gizmos only to cutout building, as the fog isn't so intelligent as to not enter buildings :- )..) and render VrayFog using Atmospheric pass after beauty render is done (with the usual tricks of no GI and full black material override).

This way, you can contrast your fog pass in post-production to such level, that in intensively cover only light beams.

[Devin Johnston]

Thanks Juraj that sounds like the best way to go.

[RyderSK]

It still might be a hassle, so rather test on still. Here's some older example from me.

You can still only include your spotlights (or the ones that have the necessary intensity/directionaly to generate a lightbeam) in VrayEnvironmentFog settings for best result (albeit, not so physically correct or natural), so it won't include the environmental diffuse light.

 

[Fooch]

Because im a post guy, i would cheat that with say optical flares and shine. loads more control..