Tips needed on using green screen hood

[rocketguy2]

I want to try some "invisible man" type effects using a green chroma key hood. Is there a different technique here than using a green screen backdrop? Any tips for shooting and keying out in post are much appreciated.

 

[clang]

With normal greenscreen, most problems centre around cleanly evenly lighting the greenscreen independently of the foreground subjects.

So when filming someone wearing a green hood (covering their whole head, I'm assuming), your lighting just got a whole lot harder - you need that three-dimensional green hood lit as well as possible without mucking up the lighting of the rest of the actor, and you still need to light the background greenscreen, ideally matching the green hood. I suspect lighting the sides of the head will be almost impossible, and you'll need to do at least some rotoscoping/masking in post for head removal.

 

[El Director]

As long as there's nothing else green in the shot, you can (to some degree) use a secondary color corrector filter to add saturation and luminescence to just the green hood, making it easier to key. And unless you have a good motion control system, it'll be easier to do if the camera is locked off for each shot so you can shoot a background plate that'll match what you keyed out.

 

[yabyum]

Interesting project here. I presume you aren't shooting on a green screen backdrop as well?

Much appreciated if you report back your findings!