Alpha Channels not working in Mental Ray
 

Hi there,
I have a tree model, it's leaves have a color node (picture of the leaf) and Alpha Transparency node (with an alpha channel map of the leaf)

Using Maya software render, the leaves render out good, with the alpha channel transparencies working fine.
When I render with Mental Ray though, the leave just look like square jpgs, showing the color maps in full with the transparency maps not working.

Any ideas on what I'm missing here?

Thanks in advance.
Rob

I ran into this problem yesterday. Under your leaf material attributes>Raytrace Options> turn down the Shadow Attenuation. That worked for me.

I'll give that a try. Thanks. I can't believe how much time I've wasted on this, until I thought to try Maya Software Rendering to compare, and isolated it to a mental ray issue

Shadow attenuation didn't work
 

Unfortunately, lowering the shadow attenuation in RayTrace Options didn't do the trick. I'm still getting the same renders, the leaves look like square cards, the transparency is not removing the edges that surround the leaf image itself.

It must be some sore of mental ray setting - I think we're on the right track. Anyone who can help, it is greatly appreciated. Thanks