*Quote - Tom, You can create an infinite plane, or an infinite slab. For the volumetrics, you need slabs. To create a slab, simply hold the mouse button for a second over the water or ground or cloud primitive on the create shelf. you will see options for surface or volume. Hope this helps.

Thank you...  I did try that but the slab was not behaving like in the tutorial..  Also he must have been working with some volumetric cloud file...  I can not find such a cloud in the contents...

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