View Full Version : Compositing-ready shadows

10-19-2013, 11:48 PM
dammit, I used to know this....

How does one prep an animation so that a white, 'void' type background can be dropped out and replaced, BUT the shadows from the objects will still be respected?

I can turn off alpha for the backdrop object but I'm not sure what happens to the shadows.... a faint memory of "preluminescent multiply blend mode" is ringing, but I can't quite get it.

10-20-2013, 05:40 AM
The ol way was to set the groud objects alpha to shadow density, the alpha then contains the shadow info.

But now... just use shadow catcher material node.

10-20-2013, 10:54 AM
Thanks RH: Time to dl the dox to this (crappy little) laptop I take to the coffee shop.

GAFFER used to have a ....thing that would allow perfect compositing of shadows on backgrounds.