need urgent help: backplane without shadows not rendering in IR

[Konichowaa]

Hi, I'm having a very urgent problem (deadline coming up in few hours):

I want to render a background plane (c4D plane with light material, for only background visibility) behind a window, but it renders black in IR or normal render when a compositing tag is applied to it with only shadows disabled? If I leave shadows on, no sky light is entering the building


any quick tips are most welcome !! stressing out here...
thanks, Koen

[thijs]

I don't have the answer, but maybe you can render a version with&without background and combine them in post?

[Konichowaa]

thanks Thijs, yes, that is my backup plan indeed, but I have 40 renders... and little time

[burnin]

If you'd care to provide a simple test scene, maybe something could be done.

[TomG]

Did you uncheck "Occlude other lights" in the Corona Light Material? Should prevent it from casting shadows. Also, if that fails, did you try the rayswitch, with GI set to empty, and the Corona Light Material in the Directly Visible slot?

[Konichowaa]

he Guys, thanks for your help

In the end I didn't find out how to do it, so I put the backplate further to the back so light could pass between it. Not ideal I know, but I just didn't have enough time to figure it out.

I'm attaching a simplified test scene with a backplate closing the terrace entirely, so effects are visible easily.

1) enabling shadows in the backplate compositing tag obviously prevents skylight from coming in.
2) disabling shadows in the backplate compositing tag, makes skylight come in, but renders the backplate black
3) removing the compositing tag is back to 1
4) disabling occude other lights in the light material allows skylight in again but renderes the backplate overexposed.
5) also disabling light emmission in the light material is the desired effect for me, but I didn't think to do that too last night... i haven't had much sleep last week :-D

 
 

[davetwo]

Just a thought. But if I were doing it, I think I would have used the Direct Visibility Override in Corona's Scene Settings rather than try and use a physical plane.

I found your file a bit confusing so didn't check you're setup properly.