Greenscreen

[Stuart C]

Hi All

 

I have been reading up on greenscreen lately. My understanding is that you need the colour to be an even green in order for the keying out to work. So in a film such as Harry Potter where they wear the invisible cloaks how is this achieved? Don't the dark shadows created by actor moving in the greenscreen cloak render those sections black and unusuable?

 

Thanks

[Scott Fritzshall]

I haven't seen any of those films, so if you could post an example it would be helpful. You don't need greenscreen to make something disappear, however, so it's quite possible that it was done in a different manner.

[John-Erling Holmenes Fredriksen]

And for shadows, if they cannot be avoided on set, they can usually be removed with a second key, or worst case just rotoscoping. A lot of shadows can be eliminated just by having enough space in your studio, so you can keep the action away from the screen.

[Jim Keller]

It's quite possible (though more difficult) to key out an unevenly lit greenscreen. But it costs you in the palette you have available elsewhere. In our studio here, we don't have the space to light the greenscreen correctly, and as a result I rarely shoot my blonde talent against it, because I find myself keying out their hair if I'm not careful.

 

All that said, I have never bothered to look up how the accomplished the invisibility cloak. May be another process altogether.

[JD Mitchell]

Hi All

 

I have been reading up on greenscreen lately. My understanding is that you need the colour to be an even green in order for the keying out to work. So in a film such as Harry Potter where they wear the invisible cloaks how is this achieved? Don't the dark shadows created by actor moving in the greenscreen cloak render those sections black and unusuable?

 

Thanks

 

That's fixed by lighting the actor too, you want the green to be almost too bright so that there are no shadow problems, I've messed around with the invisible cloak trick and when you bring it into AE you can get rid of any unwanted shadows and it works pretty well.