I have a following problem and can't resolve it alone. I'm trying to achieve the look that the object is on the table, not casting shadow but visible in reflection. Something like this:
I've already pointed the part where the problem is. It is a 3D shadow caster that I've created after tracking the camera. Here are the settings I tweaked as well as full composition view:
I can't get shadow caster to show only the logo reflection (it seems like it is reflecting some kind of black background far away from the scene (because it slightly changes when I change the reflection fallof attribute). I tried to change the background color of the composition but it didn't help at all.
I have another problem at the moment. I've figured it out how to make that reflection - put the reflection fallof at the shadow catcher to 0, precomposed all the layers, made logo only visible in reflections and now I have one layer that is the logo itself and the other precompose that is the reflection only.
The problem now is - I have my logo popping out from the floor - and before it was cut by the shadow catcher - now when it is transparent I see whole logo:
Is there a way to solve it? I spent like whole day and can't get any usable alpha chanel. For example, it could be inverted alpha of the reflection oraz the alpha of the logo obstructed by shadow caster, but any time I'm going to get the alpha, it consists of whole shadow caster. Any help here?
no exactly sure how you got in this situation, but precomposing your shadow catcher might be the wrong way to go. a shadow catcher should work if set to accept shadow only. if you created it through the Camera tracker, it should already be set properly.
make sure you are set to classic 3d in the upper right corner of your composition window (also in the composition settings->3d renderer.
we need more information, send some more screenshots but if you really want to find why you are having a problem, I recommend creating a simple setup from scratch and see step by step where is the failure.