Rendering only what's on screen

Sorry if this is a stupid question, but is there a magic button somewhere that enables, on render in Blender Internal, that when it renders it doesn’t process any geometry that’s not on screen?

I have a big animation with a lot of sub-d objects it would decrease render time a lot if it didn’t calculate not needed geometry.


Try using layers to place different groups, and at render layers tab, uncheck all those layers you don´t want to be processed.