The Camera Shader is a little plugin which can be linked to a standard C4D camera object. It then displays everything that is viewed by this camera. Thus you can e.g. make an object like a TV in your scene show some image sequence over time which is defined by a normal camera.
Of course you can also just use it to make nice effects like fractals or other funny patterns by directing the input camera to the output shader itself.
There's the possibility to change the behavior of the camera shader in such a recursion: either the normals of the objects are evaluated only once and ignored in further recursions (see "No effects" - diffusely distributed normals stay diffuse). Or the normals can be re-calculated in each recursion step which causes effects like seen on the images "effect".
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