In addition the standard outputs available via mental ray, Rendition is capable of producing extra information channels, which can be useful when performing 2D compositing on a completed render. Rendition currently supports 10 different output channels, each of which may be activated from within Rendition, without modifying the original scene.

The following video talkes a tour of the different channels.

Colour. 

This is the standard RGBA image, it may be viewed with or without alpha transparency, or the alpha channel may be viewed on its own.

 Z Depth.

This represents the distance of each point in the scned from the camera. It is output as a single channel, 32 bit tiff, unless the colour channel is selected to be output in .iff format, in which case it is combined with the colour channel.

Normal Vectors.

This channel stores a colour representation of the surface orientation, at each point in the image.

Motion Vectors. 

This channel stores a colour representation of the surface motion at each point in the image. It is only valid if motion vectors are present in the .mi file

Object Labels.

This is another colour channel, which assigns a seperate colour to each object instance in the scene.

Shader IDs.

This is similar to Object Labels, except it assigns a seperate colour to each material in the scene. This is often different to  Object Labels, since one material may be applied to more than one object, or multiple materials to one object.

Heat Map.

This is a diagnostic channel, which provides a "thermal" image of the scene, with heat proportional to the number of rays required to render a part of the scene. The temperature scale is Blue, Red, Yellow, White. It can be useful for spotting which part of your scene is slowing your render down (white parts will be slow, blue fast).

Sampling.

This is another diagnostic channel, and inserts a dotted grid overlay over the colour channel, to highlight where Rendition has traced eye rays. Rendition is adaptive, and traces more rays in areas of high detail.

 Diffuse / Specular.

These channels typically work together. They represent a splitting of the colour channel into specular and diffuse components. They are extremely useful when performing post porcessing on rendered images, as they let you modify certain aspects of the object (diffuse colour, reflectivity) purely in 2D, without any further rendering. Modification to these channels may also be modulated using the Object Label, or Shader ID channels.