Lighting advice

[ben_hamburg]

Hey there,

I am still tweaking my underwater volcano shot and I am having a hard time getting the look right.



There are two issues:

1. I´ve between the "hottest" and "coldes" parts of the smoke is a very linear gradient lighting I don´t like. The volume is lit too evenl, which makes it look unnatural to me. I´m not sure which parameters to tweak here, to avoid this.
I´d first try to reduce the overall light emission, but I´m afraid then I don´t have enough brightness at the lower part of the smoke...Maybe thats fine and I can just add some more glow in post. I´m not sure, but maybe I´ve also reduced the grid reduction for the light too much?
2. I´m having trouble getting the smoke to appear whiter, without making it overall too bright.

I want something closer to this reference:

https://youtu.be/hmMlspNoZMs?t=29s

There is only a very narrow "hot" area, and then the smoke has a very bright look right after that.

When I´m just tweaking the smoke color, the overall glow from the light emission just gets too bright, and the contrast and thus all the details disappear.
Any ideas for that?

Here are my render settings:

[ben_hamburg]

I just did a quick test and increasing the light resolution already helps a lot with getting more detail out of it.
Now I only need to figure out how to make the smoke brighter...

[LarsSonparsson]

Light resolution was really low. If I use Phoenix lights, usually the resolution stays between 5-30%. But most situations nowadays I'm turning emit light off and let the vray gi do it's magic. That way the details are well preserved.
For lighter smoke, I think you need more light to the scene. You can also increase external light scattering. At 2 it should look a lot lighter already.

[ben_hamburg]

Yeah, light resolution got rid of the "gradient" look. I remember turning it way down, since I had such a huge render impact from the light being cast on the scene and I was hoping to reduce it this way. In the end I turned off light emission on scene completely and just left it on for light on itself and just placed some more vray lights in the scene.
About the whiteness: I added more lights just including the smoke and that did the trick there. Bit of a balance there, to get it brighter without making it pop out of the scene too much. Its sometimes hard to tell whats what, if you don´t have enough reference and if you don´t know enough about the physical principles behind stuff...