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Riccardo Zanettini avatar image
Riccardo Zanettini asked ·

Using maya + arnold 4.2.13.4 Rendering a shader with opacity in AOV pass. Opacity is not computed at all. Same shader in beauty pass works perfectly. What's the problem?

Not sure what's wrong but this looks like and Arnold bug. Opacity is not there at all...

aovopacitymattes
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opaque uncheked

texture works fine (otherwise beauty won't be working)

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not a lot of people helping out in this forum

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Stephen Blair avatar image
Stephen Blair answered ·

Hard to tell exactly from that brief problem description, but I think you need to use an ai write color node, and enable Blend

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Riccardo Zanettini avatar image
Riccardo Zanettini answered ·

let me rephrase the problem

I have a shader with opacity that is driven by a texture.

If I render that shader in the beauty AOV the transparency is working.

If in the shading group node I plug the same shader in a custom AOV (let's say beauty2) the opacity texture of the shader is ignored and the alpha is solid.

I hope this helps!

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Stephen Blair avatar image
Stephen Blair answered ·

When you "plug the same shader in a custom AOV" are you using an ai write color node? Do you enable Blend?

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Riccardo Zanettini avatar image
Riccardo Zanettini answered ·

no I am not using a write color node... not sure why I would have to use and ai write color node can you please elaborate?

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Riccardo Zanettini avatar image
Riccardo Zanettini answered ·

also does the ai write node need to be plugged into the shading node?

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Riccardo Zanettini answered ·

shading group node that is

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Riccardo Zanettini answered ·

what you suggested works really well... thank you! I am just puzzled about why this node is necessary, Arnold doesn't process any of the shaders piped into the shading group node other than the surface material?

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