Scaling a Corona volume grid increases rendertime exponentially?

[wilbertvandenbroek]

Is this a bug or behaviour that I need to be aware of?
When I import a vdb cache I need to scale my volume grid to match my scene size.
Rendertimes then increase exponentially to a point where you can’t render at all.

I can fix this by adjusting the step size. Is this the right workflow or am I working around a bug?

[romullus]

I believe this is normal. When you scale up VDB object, step size remains the same and since it’s expressed in world units, not in percentage, that means much more complex calculation for Corona. Increasing step size is correct solution.

[wilbertvandenbroek]

Ok thanks for the fast reply. My smoke plumes are coming along nicely now