Z compositing problem

I want to render composite particles with halo material and meshes using Z buffers. The input files are .exr files. I have enabled Z and Combined in Render Layers. However when I try to composite them it seems that the particles Z buffer is empty. Can someone tell me what is going wrong?
Thank you,



My understanding is that unless your particles are instances of child objects, they will only be the size of a single vertex, even though they look bigger. They therefore don’t show up in the Z buffer.

On what I can see, I suppose you just duplicated the mesh and created the halo on the second one. If yes, it could be that the vertices share the same infos of Z-Depth, then all is wrong.

What if you scale up the halo’s mesh just a bit ?

Also, you can see what’s wrong using Viewer nodes directly connected to a Map Value node linked to Z.