Hi I'm having trouble with render layers and could do with a push in the right direction. I have a mental ray scene rendering with final gather and when I render layers i lose all my lovely shadow and reflection info that make the masterLayer look so good.
I have tried adding spec and shadow layers but this doesn't seem to work.
I've found that with maya it's not so much hard just illusive:)
I've run into some problems with mental ray and render layers too. Sometimes the only way to get proper results is to render just one layer at a time (i.e. uncheck all the other layers' 'R' flag in your render layer palette).
the trouble with this is because all the materials interact with each other to give the final look you end up with flatish renders with no reflection or subtle shadow and specular when you turn off the other elements.
at the moment I'm doing a flat render as insurance because I have a dead line to keep. but would still love to know if I'm missing a trick here?
Hmm, maybe the difficulty you're having is something different.
Let me ask you: why have you broken your scene up into layers? What's on each layer? Are you separating background, middle, and foreground objects? Or are you separating diffuse, specular, and shadow info? Or both? Or something else?
For reflections and shadows, be aware that you can include objects on a layer but uncheck their 'Primary Visibility' attribute. This will make the object itself disappear, while leaving it able to cast shadows and/or appear in reflections on other objects and so on.
I'm separating a pack from a background, I just needed to be able to composite something between the pack and the BG, I got round this in the end with a geometry matte.
however the primary visibility option you mentioned would do the Job perfectly and with more flexibility to move it around in AE as well so I guess that info is the nudge in the right direction I needed.