Keying out with extreme mnotion blur footage

While blue/green screening, is it possible to still key everything out properly when the source has extreme motion blur? All the tutorials I've seen seem to suggest to me that it isn't possible, but something tells me that it must be possbile, otherwise film effects would be damn hard to do right - and action film footage especially.

 

Well, I assume your motion blur is a result of fast movement, perhaps Lightsaber Combat, right?

I suggest choreographing everything and film it with the actors doing it slowly, then speed up the time in post production, like reduce the film rate from 30 to 20 frames per second. They'd still move fast, and the blur would be down. AND you could add blur later.

EDIT: Is that the issue?

 

Yes it is very possible to keep motion blur in your composite. It does require some extra masks, but it definitely is possible.

Tim

 

You could always film your actors using the high speed shutter but if you were using sabers they wouldn't fan out & may look very cheesey

Mushi

 

I put the highest priority on maintaining motion blur -- it's critical to a good composite for action sequences. As Obi said, it will probably require separate treatment -- but you don't want to do anything to eliminate it. Our eyes have been trained to expect motion blur -- when it's not there, we notice. Now, that's not to say that high shutter rates can't be used to achieve neat effects (Saving Private Ryan, for example), but unless you want that hyperkinetic feel, totally avoid it, because it's going to make your compositing efforts more difficult in the long run: people will likely spot the composite more easily, and chalk the lack of motion blur to poor compositing rather than an intentional effect.

 

Dave is so the man these days

Pete

 

Tools like Commotion are especially suited for these. Not only can you feather rotosplines but in the latest versions you can apply motion blur to them.

 

Also, try just keying out the back color and using a spill suppressor on the motion blur.

 

I don't know if it'll help, but at DVGarage they have a few short movies in the Composite Toolkit about getting masking blurs. I may help you figure out the rest.