Hello,

I was wondering if anyone knows if it's possible to use an object to occlude a light source without that object getting rendered too?

Meaning, making it ‘invisible’ to the renderer but not for the purpose of saying using that object occlude a light source that would say, result in a shadow on another object.

I suspect I will have to get into doing compositing. But for the time being would prefer to just work with lights and objects somehow.

Thanks.

Geometry node -> Render tab -> Render Visibility -> Phantom

Not sure if this is what you want though.

Thanks for the suggestion A-OC, unfortunately that doesn't seem to do the trick.

Could you rephrase then ? I'm not understanding your question as it is.

Perhaps I should include a hip file.

But say I'm looking at a sphere from camera view.

I also have a spotlight looking down at the sphere as well; from the same direction as the camera.

In between the sphere and camera, I place a flat disk to partially block out and caste a shadow on the sphere.

However if I render from the camera view, that disk object blocks out a part of the sphere from being seen ( blacked out because I have the light filter of the disk object blank so it receives no light ).

I would like to be able to caste the shadow but not have the disk obscure the view of the sphere.

Then Phantom does exactly that. I'm feeling a little dumb now, lol. Maybe post your hip file.

look

Ok…here's the file.

Phantom doesn't work…but -primary does.

I thought I tried primary earlier, but I guess I overlooked it.

Thanks for your replies A-OC….making the hip file got me to try -primary again.


I can now work on mapping a transparency gradient to the block disk - more opaque towards the middle, and transparent towards the edges so that the shadow goes from dark to diffuse

Yeah..just seeing your posted image…I don't get that with Phantom.

Well Phantom is the same as -primary . I just called it like that because that's what it was called in previous versions

I didn't mean for you to type Phantom, but rather to select the option from the drop down.

Yeah..thanks for your help