Render mattes only

[sherridge101]

Hi all

Is there a way to render out mattes only across a sequence of animation frames?

We want to avoid the render hit for the beauty etc. (as we have already rendered the beauty), but just output a few different mattes across frames.

We've tried:
Assigning a light mtl to the beauty, but this gives noisy sample on the motion blur.
Lights off in the scene, but again, we get noisy motion blur edges.
And we've tried 'Don't save Image'.

Cheers

[Morbid Angel]

You need to provide the sampler information so the end image is not noisy. Since the sampling is performed on the rgba you cannot make it a solid color as it will use only min samples. The solution would be to use something like a frenel texture in the light mtl, and increase min subdivs to 3 or 4. If you have strong motion blur though you might need to go higher in subdivs (for the sampler)

[sherridge101]

Hi Dmitry

That worked a treat, thanks.

Cheers

Steve