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Help with live action footage and CG (reference video inside)


I came across this video and writing script for my next short, these shots are extremely similar to what I am looking to accomplish.


I will have numerous shots of similar composition with set extensions.

In the video, the camera is locked down (just like in my shots) so I don’t need to use a match mover. Only the person is green screened, as everything else is non moving so it’s easy to use a pen tool and mask out around the edges of the cliff/hill or w.e

But how do I go about creating such an extension and making it work with live footage?

We’ll use the shot at: 2:31 – 2:45 , we’ll use that as an example.

My idea is this:

1. Take my footage into After Effects and using pen tool mask out or cut out around the rock/cliff edges.
2. Key out the person on the greenscreen
3. Get a snapshot of the frame with only cliff/rock edge masked out as well as my keyed out person.
4. Bring the snapshot of the frame(step 3) into Cinema 4d
5. Create my 3d models (most likely hills and trees, maybe birds flying) in cinema 4d.
6. Render out JUST the cinema 4d modeling
7. Bring my footage and cinema 4d set extension into after effects and place one on top of the other and align.
8. Color correct to hide the imperfections.

Is this the correct workflow?

Also looking back at 2:31 in the video, is set extension a 3d modeling or is it live footage? Also, water and waves? Is that possible in cinema 4d? is there a plugin?

And, is there any particular reason why they converted greenscreen to blue color aside from the illustration purposes? Is that something that I need to do as well for any specific reason?


if its all non moving shots, then why even 3d models? This is CLASSIC set extension, not 3d. Good matte paintings (digital or otherwise) is all you need.

This is not to say you cant use 3d apps to create your set extensions, but you don't NEED to as there is no real 3d interaction.

I found this article remarkably inspiring.


Also, some info on classic filming techniques, masking IN camera etc ..


If your WELL versed in 3d apps and what not, you might very well PREFER match moving, in which case camera movement is your FRIEND. You can do a camera solve with parallax motion much easier, but thats just academic to me, as Iv never done it..
I would say avoid doing landscapes and especially water as CG if you can, as its super easy to look rubbish, and very very hard to get it to look realistic. May also require a render farm if you want to see it high quality more than once a week its so computationally heavy. Do it the way these guys did it as much footage as possible, it will save you a massive amount of time/effort even though it may not seem like it.

As for the blue when they do the green screen, I think its just green suppression perhaps? But its still just a key, so dunno why they showed that.