Hello. Long time no see and all that fluff.
I have been working on bachelor for a long time now, so time has not been in ample supply.
Apparently, to get the best result with your zdepth layer and depth of fielld, you need to render your images in double the final size and the zdepth layer must not be anti-aliased. I haven’t seen a convincing example of why not yet, but it makes sort of sense so I am willing to play along.
Problem is, we use a custom mentalray shader for DOF and mentalray has not been very happy to refrain from anti-aliasing the zdepth layer. Even setting min and max samples to 0 didn’t do the trick for us.
In the end we found that you also needed to set the filter type to traingle. A width and height of 2 is fine, but you need the triangle filter.
You hear that google? No anti-aliasing in mentalray by using triangle filter with 0/0 samples!
Now to solve that render layer crap.