Greg Hughes

After copying the Pyro Shader from SOP level to the Material Library in Karma to render an explosion as it appears using Mantra at the SOP level, I find that the shading is very different. Is this unavoidable because of the difference in the renderers? Must I again adjust parameters to get a similar look or is there a simple fix that I am unaware of? I find I need to adjust light intensity and the parameters in the Pyro Solver to get a more similar render in Karma. Tutorials I've watched just copy the Pyro Shader without changing any parameters -- but this no longer seems to work in v20.5, it causes shading problems. Instead you have to select the Pyro Bake Volume node at SOP level and in Quick Setups button select Create Material-Custom Location and select the Material Library. This creates a new Pyro Shader network that works properly.

EDIT: I think I found the problem, an Environment Light that was not enabled in viewport. But do I need to set anything to render out to retain the same ACES colour space for use in Nuke, or will it do so by default?



When I render with Mantra in ACES colour space the render looks very bright, unlike the viewport representation -- see image:

https://i.postimg.cc/k5b8gWpg/ACESManta.png [i.postimg.cc]

I have set the Render Working Space to ACEScg and View Transform to ACES 1.0 - SDR Video

Is there a setting in the Mantra node I need to look at?

I have not had the same problem rendering the same thing in Karma.

I am familiar with the old Pyro Shader node, but have come across the Karma Pyro Shader node in Solaris. What, if any, are the differences and advantages of using the Karma Pyro Shader?

The old Pyro Shader has a useful button for adding passes like pyro_scatter to Mantra but this does not function with Karma.

I can only see the C_emission AOV for view in Karma if using pyro Shader material, so presumably this is all you have to use?

The Karma Pyro Shader, however, adds aov_scatter and aov_fire AOVs for use. You also still have C_emission AOV.

When compositing an explosion in Nuke, do you generally just use C_emission and the various light AOVs to recreate the beauty pass for an explosion?

What would be the use of the aov_scatter or pyro_scatter AOV?

Also, What is the combined_volume AOV used for?