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When compositing I often notice the shadows in octane on matte objects are, well, uncontrollable. Every matte object in the scene has intense alpha levels/shadows despite it being a basic daylight scene with no obvious objects casting shadows onto the matte objects. So when you composite you get lots of black patches in areas you would not expect them. A character I'm compositing has extremely black shadows underneath his feet and there seems no way to control shadow density. They wouldn;t be that 'black'.

Of course controls for the shadows on matte materials would be nice, but as useful (maybe more so) would be the ability to render out a shadow pass so we can have much better control of just these layers when compositing. I'd really like the flexibility to adjust the shadow strength in post, or even blur or mask around shadows I do not want visible.

Hi Darkline,

I have a couple of suggestions that may or may not work for you (depending on what your doing).
1) Change the opacity of the matte material, this will reduce the alpha of the shadows, effectively softening them. The only side effect of this is that you will see through the matte material so if there is any geometry behind it, that may cause problems making this not an option.
2) Use the material ID mode of the deep channel kernel. This will give you the ability to accurately create a mask in post for the matte material only, so you can isolate it and reduce opacity or whatever you want.

Thanks
Chris.

Hi Chris,

Thanks for the suggestions. In this particular case 1 won't work as there are matte objects behind but that's actually a very helpful workaround for some scenes I can think of.

I'll give 2 a go, never done this but are you saying to use the material ID image as a 'set matte' for my main render in After Effects? I'll have to have a play because I'm not sure of the workflow.

Are you considering implementing shadow passes at all, or more options for matte materials and shadow control?

Hi Darkline,

I'm not sure exactly what you would do in After Effects, but what the material ID pass will give you is something you can use for a mask, so that it is easy to separate out different materials in post (so you can tweak only certain materials). I was hoping in this case you could isolate the matte material in post and reduce the opacity, therefore reducing the shadow strength.

Sorry, i can't comment on the roadmap for passes. Obviously, we would love to do everything that is asked but in reality we need to prioritize!

Thanks
Chris.

Understood, and thanks for the help.