Blenderpedia dives into image composition and layer rendering in this video tutorial.
Rob Tuytel writes:
When you create a scene in blender, you can finalize this in the compositor. This makes it possible to combine multiple render layers but also different scenes. The Blender compositor is a very powerful tool to upgrade the scene and to explore the possibilities.
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I have a LONG history with Blender - I wrote some of the earliest Blender tutorials, worked for Not a Number and helped run the crowdfunding campaign that open sourced Blender (the first one on the internet!). I founded BlenderNation in 2006 and have been editing it every single day since then ;-) I also run the Blender Artists forum and I'm Head of Community at Sketchfab.
