correct way to use Render Layers Shadow passes?

[Dingbat]

please can someone help

let's say i have a simple room with a sphere in it. if i render the room i have this:

now i add a 'cube' which casts shadows on the sphere:

how do i render only the shadows that are cast by the cube?

i tried the Render Layers BlackLayerShadows and LayerShadows but i get this, which looks like the walls of the room are being ignored?:

i should be getting something like this:

am i going about this the right way?

how do i get a shadow pass like the last image?

[Dingbat]

so is Octane "support" always this good?

i'll try one last time

i have attached a simple scene. is it possible to isolate the shadow made by the sphere?

IsolateShadowIssue_01.orbx

(464.83 KiB) Downloaded 94 times

[Hesekiel2517]

I'm also wondering how to do that. Can't disable self shadowing of my shadow catcher. Any suggestions how to do that?

[Hesekiel2517]

Ah found it. You have to tick shadow catcher in the material. In my opinion it should work without doing that, but at least it works

[Hesekiel2517]

i just want to add that this works, but disables the layer reflections. So mybe there is room for improvement