how to composite LIVE action into 3D and not the other way around??

[Jim Scott]

The reason you can’t find tutorials on compositing green screen footage with 3D objects in C4D is because that is not how it is done. Very simply, AE is a compositing program and C4D is not. The tutorial you referenced was showing how AE was used to composite green screen footage with other background footage. To combine your piano player footage with a piano created in C4D you would export your piano from C4D into AE using Cineware and composite there… not the other way around.

https://helpx.adobe.com/after-effects/using/c4d.html

[Tudor “ted” jelescu]

You should always think as compositing 3d elements in the live action footage, even if in the shot the live action element is one actor/object and the rest is 3d. You need to export your 3d elements matching the camera move, space arrangement and lighting and then comp them around the keyed out live action element. Plenty of tutorials for that.

Tudor \”Ted\” Jelescu
Senior VFX Artist

[Adrian Chircu]

I gave it a couple of tries with some tuts on YT. Managed to stick a piano to the ground and then key out the green screen and it looked.. well, weird.

The piano placement was correct though and the scene was correct in terms of compositing, the looks however were horrible. I`ve tried to color correct, shadows, level, etc, basically the whole package. It did turn out better but still not on the level I want it to be.

Now, I don`t want to make another thread so Im just gonna ask this here, please read everything, it would help a lot!

What would you do if you had to add background to your shot and also a fake piano? I thought of two options, the first is to actually work with 3D objects and the second is to work only with 2D objects, meaning that I would render the image of the piano and the background rotated according to the live footage camera`s position so it matches the scene.

ALSO, what would you do if you had to choose between zooming in the actor while filming, thus having camera movement and requiring tracking OR have the camera on a tripod and zoom in post losing quality as you zoom closer, what would you choose?

ALSO, this is the last also, I promise. I have to add flames that stick to the piano`s legs and that eventually grow bigger up until the point where the whole piano is covered in flames, OBVIOUSLY this is going to require a lot more work, because the flames add lighting to the background and they should actually BURN the piano and not just “hover” it making it totally unrealistic. What do you think would be the best approach to this? Do you think its worth as a total to add flames? What other visual effect to add intensity would you add that might be actually easier?

Thank you!

[Tudor “ted” jelescu]

To get a realistic feel in your composite shots you have to blend the CG elements with the live action ones using light, reflection, color, space and so on. Videocopilot has quite a few tutorials where you can pick up tips from.
To answer your first question – it all depends on your workflow. If you want to have the possibility to change things to the very end, use 3d objects. If you are set on a look and can work out a workflow that does not need tweaks on the 3d objects until the very end, you can choose to render the background and piano and then composite all with the live action.

Definitely camera move – you do not want to loose resolution.

You can maybe add energy/lightning discharges on the piano using Saber (Videocopilot). Whichever way you go, you will need to take in account the reflections from the fire/energy on the piano and on the environment and actor. So for the 3d elements you will need to create those reflection in compositing and by adding animated lights in the 3d model. For the actor you need to plan practical effects (led lights that move around reflected from metal foil that move on the actor for example).

Hope this helps

Tudor \”Ted\” Jelescu
Senior VFX Artist