https://i.ytimg.com/vi/oveSskhIEAc/hqdefault.jpg

Blender tutorial showing you how to render your interior scenes in a fraction of the time: http://www.blenderguru.com/tutorials/using-portals-accelerate-render-times/

Discover a new feature in Blender 2.75 that could save you hours of render time – Portal lamps! They help Blender understand your scene, and thus speed up rendering significantly.

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