Export shadows only of an objects set

[98%.cgi]

Hi everyone! First post here!

I'v got a complex task from my customer and browsing in the internet I've found very little hints about. Here's the thing (see attachment):

They would like to modulate the intensity of shadows of handles and knobs only, because they cast on the kitchen doors "oddly", in their opinion (but not in mine).

In my logic, I think this could be accomplished like having on a separate layer (.psd, .png, or anything with transparent background) the shadows and then installing them on photoshop and build the result there.

I've tried to understand the concept of Shadow Catching but since I've got a very complex scene, with multiple handles in very different positions and lighting, it will take ages for me to build singularly the shadow catching planes.
Is there any way to accomplish this with something, I don't know, like Multipass or similar?

Many thanks to everyone!

Cinema 4D R25.015
Corona Renderer version 9 hotfix 1

[romullus]

Hi and welcome to the forum!

I'm afraid, there's no easy way to control shadow intensity of specific objects. You could try to use rayswitcher with separate material plugged to GI component and reduce opacity of that material, but i doubt that you will like the result.

I agree with your client the shadows from the handles looks bad indeed, but it's not the fault of inaccurate physics, it's the fault of bad lighting. Try to move the light source, so that it wouldn't sit directly above the handles. You can also increase light's area, so the shadows it's casting would be more soft and less pronounced. Try to approach to the issue in a way that photographer would in a real world scenario.

[98%.cgi]

Thanks romullus for your reply!

I'll make a try with your tips. I know that Corona is physics-based and I'm glad for that. I think the light sources, as you say, are the issue here.