Domain Artefacts in Cycles Render

Hello friends of Blender,

I have made a flame with a candle in cycles.
After rendering I have some white artfacts in the shape of the adaptive domain as you see in the pictures below.
Can somebody tell me where that is coming from.

Thanks in advance for help.



Try adding
a color,brightness contrast node between the flame and colorramp and adjusting the values.

Thanks Photox but it doesn’t remove the artefacts

Try using a Greater Than [Math] Node to remove the edges of your simulation from the equation:


This eliminates all the flame data that is nearly zero (or actually zero).

Without access to your blend, it’s hard to say more. Maybe you have a transparent shader applied to your surface, and you don’t have enough transparent bounces enabled. (In which case, you should remove the transparent shader entirely!)

Ok, well I have this same problem. I tried your solution, didn’t work.
here’s the image
Can someone help me out here, please? What can I do to make the outline disappear, or is it not possible in cycles?
Here’s the blend file

Holy smokes, your scene is very, very small. Your smoke domain, for example, has a scale of 0.006. My guess is that the problems are caused by rounding errors that can take place whenever you’re working with complex math and super small numbers.

For instance, once you get to 0.000000121 (or something like that), the computer might round it to .00000012 and just leave off the ‘1’ at the end. Normally this doesn’t matter (computers can’t calculate an infinite number of decimals; it has to stop somewhere), but when you’re working in such a small space to begin with, those super-small numbers DO start to matter, especially when dealing with complex math, like a smoke sim.

The following test fixed it, though you’d have to make tweaks to your entire scene for this to work:

  1. Only show layer 1
  2. Select the camera, Shift+S “Cursor to Selected”
  3. Period key ( . ) to set the pivot point to the 3D cursor (everything rotates/scales at your camera, thus)
  4. Enable visibility for your rig
  5. Select the rig and the domain, S + 100 (scaling up these elements by 100, with the camera as the pivot point)
  6. Play through the animation or otherwise re-bake the simulation

This eliminates the nasty edges (though it has created other problems, basically things that need to be adjusted for the new scale):

Before:


After:


Sometimes just selecting the offending mega-scaled items and pressing Ctrl+A --> “Apply Scale” does the trick. Your rig is also extremely small (a scale of 0.036) and your smoke emitters belong to the rig, which ultimately makes them extremely small as well. So I tried unparenting your smoke emitters, removing all keyframes, and Applying Scale to the Domain and the Smoke Emitters, which didn’t change anything.

Thus, I think this issue has to do with the fact that you’re forcing Blender to work this smoke simulation in a very small world space, thus with very, very small numbers, which is creating rounding errors, and leading to the funky edges.

Hope this helps! Good luck!

Ok, so I cleared the smoke domain from the parent, applied the scale, brought the scale up to 1. Still didn’t work…