MILA Passes

Today I had another look at render passes and compositing them together. I started out with this just to refresh myself.

I used all MILA materials from Mental Ray 2016, I really like using them, they can be versatile and I like the layered setup, and the results are pretty good and render quickly. Recently we learnt a more efficient way of combining the passes, without shuffle nodes which I was using before.


I rendered the passes from Maya into an EXR, and composited them in Nuke like so:


The only problem I ran into here is the weird blotchy visibility of the lights in the reflection of the sphere.


To take this a little further than what I had done before I looked at Matte ID passes. I used them to change the colour of the cube in post, here's it is before the change:

 (I have re rendered the image with a grey plane in Maya)


And here it is graded:


Here's the tree:


Setting it up was as simple as plugging in the Matte ID pass for the cube into the colour correction and grade nodes as masks.

Although this process isn't ideal, it's useful to know that using a Matte ID pass you can have control like this, even if you needed to re render something and replace it, rather than just altering it in nuke.

Here's the final graded image:



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