Composited Multi-Speed Action
Posted 10 May 2012 - 01:49 PM
My main question is should I shoot the moving actor on a greenscreen at 24p and the bg separately at 300fps, or do you think it would be easier to do some rotoscoping when necessary?
Or maybe I have no idea what I'm doing and you can think of something better. Perhaps bottom line...do you think this shot should be entirely 3D? Or is there some possibility of pulling off most of it in camera?
Right now I'm leaning towards shooting the normal speed moving actor on a greenscreen then shooting/creating the background to match.
Posted 10 May 2012 - 11:19 PM
Posted 11 May 2012 - 02:26 AM
But i think Gregory covered most of it
but from what I can tell you would want to shoot your actor on a green screen and shoot bg plates, with each character and or object shot as separate plates so you can have more control when composting, you want the character be at normal speed then just shoot him at 24fps and the rest at 300fps, could try even shooting your character at 30 or 40 and then slowing back down to 24 just so he doesn't seem so out of place, but that's just a thought
Posted 16 May 2012 - 09:57 AM
We have two people in this scene ( a man and a woman), and 3 zombies. We are in a church sanctuary. An explosion has just happened. The walls are burnt and there is ruble on the ground. The woman is lying on the ground in ruble. Zombies are approaching. She has a gun, but can not aim very well. She takes a shot, but it's not going to hit anything at first. Now, time slows down to a crawl. The man has super speed powers and looks over to her, then the bullet. He appears to move at normal speed as the bullet slowly travels across the scene. He walks over to each of the 3 zombies near the bullet, and moves them into the path of the bullet. Time now speeds up as he moves away from the zombies and we see the resulting triple headshot.
Oh, and to throw a wrench into the whole thing, all the explosion/debris/damage to the church has to be VFX. We can't actually burn the church (unless you know a way to do it with set design, I guess that might be a possibility)
If you have any tips on how to make this shot happen as simply as possible, let me know.
Posted 17 May 2012 - 09:03 AM
Posted 27 May 2012 - 02:13 PM
Using this technique means you can move the camera around and you don't need to do motion control passes at different frame rates or even put up a greenscreen (even at the high-end of vfx, it is still hard to make greenscreen shots look good). It does however mean that you need to remove any elements in the shot which could give away the 24fps frame rate - ie... fire, smoke, water, dangling hair, etc.
For the burning church you might be able to get away with a Pepper's Ghost http://en.wikipedia.org/wiki/Pepper's_ghost style effect, but it'll probably be easier compositing high-speed flame elements.
Hope that helps.