When using subdivision, each level divides each poly to four polys.

so, if you have a model with 4000 polygons,

SubD 1: 16,000 polygons SubD 2: 64,000 polygons SubD 3: 256,000 polygons SubD 4: 1,024,000 polygons SubD 8 :more than 260 million polygons.

Usually going up to 2 is enough, 3 is plenty. More is rarely needed.

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Sail out to sea and do new things.
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