Simply Maya User Community

Simply Maya User Community (https://simplymaya.com/forum/index.php)

- Lighting & Rendering (https://simplymaya.com/forum/forumdisplay.php?f=17)

- - Render Layers (https://simplymaya.com/forum/showthread.php?t=8957)

I'm having a problem with rendering in layers. It seems that Maya makes the alpha only from the transparancy channel and doesn't take into account the reflection or highlights. That sucks! I need to render in layers, but cannot get it to look like my test renders.

Does anyone know a hack around this problem?

You need to render a specular pass to get the highlights.
As for the reflections you have to modify you scene manually to output the reflections only. Then composite them afterwards.

You might want to take a look at this: http://www.technolumiere.com/software/renderpasses.html

How do I make the scene only output reflections?

Check that site I posted. Download the plugin and learn how to use it. It comes with an example scene which you will be able to learn from.

(You will need to write some simple mel though)

OK, I get how to use the tool, but I'm still not sure how to write something that says only render reflection channel. Do I have to create a new material for this?

Just fyi from the docs:

Quote:

Note:
No mask or alpha channel is produced for the Specular Pass, so we recommend additively compositing a specular pass.

Custom shadow and reflection passes
You can also create custom shadow and reflection passes with the useBackground material which catches shadow and/or reflections.
When the shadow pass is rendered, a black image is created with mask channel that contains the shadow information. A compositor can work with this channel to blur, lighten, darken, etc., the look of the shadows.

When the reflection pass is rendered, an RGB image is created with a white mask in the mask channel.

To use the Use Background material to catch shadows and reflections, see the Lights and Cameras guide.

Does that help a little?

Also, Kbrowns link is a great one to try also!