Previz is the "digital storyboard". Anyone who animates uses a storyboard to set framing and general "look and feel". Previz comes handly when you have to check your timing. Even when you playblast an animation just to see "how it looks" you are using previz. Unless you just rendered the images using the "here goes nothing" motto :-) without even playblasting your anim once.

nemirc
Renderosity Magazine Staff Writer
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