High contrast scene, full body, against Green Screen?

[Markus A Ljungberg]

How would you light for a wide shot, full body, on green screen, if you want to achieve a high contrast look?

 

I'm dealing with a scene where 10-15 people are dancing and performing a ritual. The main light will come from a big fire and torches (Will be added as CG), so ideally the shadows should be deep, 1:16 ratio, some shadows close to being crushed. A subtle cold light will come in as ambient. How would you light for this against green screen? For the tight shots it's pretty straight forward but I'm trying to figure out the best way to deal with the wide shots. I will definitely see feet on the floor.

 

Our CG supervisor says that I don't need to worry about dark shadows on the floor, as they will be brought into the final comp, but they obviously can't be crushed. And I still need a reasonably even light across the floor.

 

My plan at the moment is to using space lights to bring up the ambience and to light the floor just enough to enable a clean keying (But less then the conventional 60-80fc), and then have the lights mimicking the fire a good number of stops over the ambient level and also a lot warmer, close to 2xCTO. In post the floor can then be keyed properly, and then after keying a LUT could bring my contrast up to where I want it to be, and with the RAW format I could cool down the shot to make my the tungsten ambient appear cold and the fire warm. Is that a sound plan? Is there an easier, better way do to this?

 

I'm definitely loosing out on some of the latitude of the camera with this approach, and as I like to achieve the look I want in camera it feels a bit awkward to rely so heavily on post. Unfortunately there's no budget for a test shoot.

 

The size of the studio is W: 45' x L: 55' x H:16' and I have a grid over the entire set for rigging lights. Shooting with Red MX.

 

All advice much appreciated, thanks =)