Shadows on grass in live action footage

Hey, I’ve got an extensive vfx project, but I came to the realization that I’m not sure how I would composite shadows over grassy areas. Any idea on how thats possible?

Use the “multiply” node.

Well, I know how to put shadows on top of areas, the real problem is the distortion of the shadow because its on grass, so the shadow isn’t gonna just be flat.

Here is good Tutorial.

So that is replace grass with shadow?

How about cast shadow onto simulated grass but give the grass a receive shadow only material so that all you get is the shadow cast on grass shapes. Wouldn’t be good close up (incorrect overlay) but at mid ground would probably be roughly correct.

Hey guys, thanks for helping me on my compositing adventures again. Yeah, I guess I’ll have to create grass then for the shadows :stuck_out_tongue:

Really only around the edges where the grass shade is a different shape. the rest of the shadow would be uniform.

Yeah, I just wasn’t sure how to make it match… the live action footage grass :P, but I guess it doesn’t matter, as long as the edges are distorted

Movies are just an illusion anyway (25-30 illusions per second), so if it looks ok it works. People don’t pause and pixel peep really.

Try and match a significant item though, say a rock or large tuft of grass or low shrub. People will ignore the rest as they will accept the one good cheat.

Yeah I agree