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When you work with “Cell size” and objects you also have to take the object's “Volume” panel into consideration. There you will find another “Cell size” value, but this time for the rasterization of the colliding/interacting object. The associated Hybrido domain provides a “Cell size” value as well. By default, all these different size are parameters share the same value.
Max particles
This parameter provides a very convenient method of controlling the number of particles, although it is rarely used. When the total number of emitted particles exceeds this value, the emitter will not be able to create more particles and emission stops.
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