subsurf render problem.

hey peeps,

How come my cool shiny rings are normal size when I render with out subsurf modifier, but they triple in size when I do. Weird.



That’s just what happens with subsurf… Turning a mesh into a subdivision surface is - in a way - like putting the whole mesh under tension. Every edge that is not held in place by supporting edges will get pulled apart.

so what can I do?

Add supporting edge loops to “stabilize” the edges you want to have tightened.
Ctrl-R at the indicated positions at then move the newly created edge loops towards the existing edge loops:

BTW, that mesh is a bit wonky on the inside. A W > Remove Doubles finds 64 doubled vertices. There is an addional face ring in the inside where the mesh kind of folds in on itself. Remove that, too, and then do a Ctrl-N to recalculate the normals.

Cool, thanks. I will play with it. I did try putting in edge loops but it didn’t work. I’ll try again.