Render Passes

Everyone talks about render passes. So I figured with the live brief project getting quite big, as well as the composting of the smoke effect and oil rig it's time to learn about them.

 In Maya 2016 Mental Ray is no longer bundled with the programme. This meant there was a big change to how render passes work. Mental Ray passes now all work from a new MILA shader.

 This shader is layered so instead of picking a standard shader that allows reflection, or no reflection for example, you always pick the MILA material and add reflection if you need it.

 I set up a simple scene with some reflection and specular, based off a tutorial and lit it with the Sun and Sky lighting in Mental Ray.


To use the new render passes you need to use the MILA material on the objects in the scene. After playing around with the material I created a quick scene with reflections, added some passes and added them into Nuke. I rendered out EXRs so that all the passes were combined into one image, this was really useful.

The process of bringing the individual passes out of the EXR and combining to re-create the "beauty pass" was quite simple. I quite liked it because I was able to clean up some noise on the specific passes.

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