How to make the fire smoother in cycles?


I’m trying to make my fire simulation (cycles) look better. Now it has this “blocky” noise with vertical and horizontal streaks.

My emitter is set to only generate fire.

These are my basic settings:
Resolution Divisions: 152 (pretty high I think)
Smoke high resolution Divisions: 10 (max)
Full samples (best?)
Strength: 2 (don’t know what this does)

Any other settings that might be interesting and could explain the blockiness?

The noise does not seem to be created during rendering. I’ve tried 100 sample passes without improvement.
The blockiness is only noticable when animated. This is a screen shot from the clip showing what I’m talking about. (I’ll try to upload a video later)

Hope you can tell what I’m doing wrong.

Best regards, Erik

Here is another example:

Which setting do I need to improve to get rid of those vertical and horisontal lines?

Here are the current settings.
Smoke domain:


Here’s the blend-file as well.


eld_animated_logo_06.blend (906 KB)

It’s about expected considering how large the domain is. It’s ~21.6m along it’s longest side, you’re using base res=200, hi-res=2, so that gives you a total res of 600 along the longest side. 21.6/600=0.036. or 3.6cm. That’s definitely a lot bigger than pixel-sized. Why is the domain so big? It seems to be a lot larger than the area your emitter moves through. I’d recommend making the domain no bigger than it needs to be. Than increase hi-res divisions if things are still blocky at that point.

Thanks J_the_Ninja!

I didn’t know that the size of the outer domain boundries was an issue. Or that the base resolution was effected by the domain size. (That makes a lot of sense now that I think about it…)

I can probably make it smaller and maybe look into how to make it follow the burning ball around the scene. (I think I’ve seen a tutorial with a moving old steam driven train with smoke coming out of it.) Right now I’ve made the domain big enough to cover the ball’s entire movement.
But I though checking the “smoke adaptive domain” check-box would solve any issues with having a really big “outer” smoke domain.