View Full Version : Black alpha borders aroud objects when mixing MR and SoftwareRender in RenderLayers

01 January 2007, 02:41 PM

I have something really strange here in my scene:

Im using a HDR image that looks very cool for my heaven.
So, on my first render Layer, there is only the heaven and it is rendered with Mental Ray.
On the second render Layer above, there are all other objects of the scene, some canyons and trees etc... This layer is rendered with Software Render.
When I choose Composite Layers in the Render View, the 2 Layers are composited, the objects over the Heaven, but there is a small black edge aroud the software rendered Objects, right there where they lie over the MR heaven...

What is up there?

Can I avoid the black alpha edge somehow?

Thanks a lot for help,


01 January 2007, 03:05 PM
for whatever renderer you use that renders out the passes OVER the matte you have to uncheck "premultiply".

In the mental ray render globals uncheck the optione "premultiply" in the "framebuffer" section. In maya software render the "premultiply" option is in the "render options" tab.

That should get rid of the nasty black border.

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01 January 2007, 03:05 PM
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