Steadicam and Greenscreen

[John Sharaf]

David,

The shot you’re describing can really only be done with a “motion control” camera, where the movement of the camera for the foreground can be recreated whilst shooting the background and then composited together.
You would of course use a green screen (or other color) to hold the window out and I like your idea of some intermediate foliage behind the window and in front of the screen (thus requiring another color other than that in the foliage).

The only other alternative of course is to shoot in a house in the jungle with three windows!

The use of a Steadicam precludes the ability of recreating the exact movement for both the foreground and background, unless you use plan B (shooting in house in jungle), although the motion camera movement can be programed to recreate a floating or handheld quality if that is part of the illusion.

Sounds expensive in any permutation.

JS

[Angelo Lorenzo]

I disagree with John; I think he’s picturing a set up that is FAR more ambitious than I do.

– Choosing flats over location, I think is more of an issue with set dressing. I’d place a green screen outside of either and do fine. If you shoot on location, you may want some additional lighting to bump up the green outside the windows if you’re on the shadow side of the building. Green screen usually keys best if it spots +/- 1 stop from your ambient; this is assuming you’re night lighting too high or low key.

– How big are these windows?

– I assume you’ll be on a mix of lenses, so I would place tracking markers at two depths: I would put an orange tennis ball on a green pole about a foot outside the window, and I would put some dark green tape X’s as tracking markers on the green screen and place it 6 + ft out from the window.

This set up won’t allow for a really push-button key (you’ll have to roto a bit) but having tracking markers at two different depths will help you track parallax. You could have foreground elements and then a background plate projected in the distance.

– Depending on how tight your tacking shot is, you can mask your actor out of the frame and run the camera move through a camera tracker. After Effects has some 3d camera tracking plugins available, Maya includes Match Mover (excellent, used it to insert 3d characters into live action footage for tv commercials), Synth Eyes, and so forth. You can use that move to track a camera over a background plate and then use that animation in the key.

This stuff is a bit difficult technically, but it’s not wildly expensive. You rarely need motion control rigs for simple compositing like this.

Angelo Lorenzo
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[David Smith]

Hey,

Thanks for both of those really helpful replies.

I will probably go with what Angelo said and run some tests with it.

My friend has planned on shooting the shot on just one lens so I think I’ll just stick some crosses on the blue screen and composite it afterwards in AE 6. Or would you recommend keeping the ball and the pole and sticking a second layer of jungle to it?

Thanks so much for the help again.

David