Shooting with a Green Screen
One of the projects we are currently working on is a sequel of sorts to a historical video we produced last year for a library's local history video project. Last year's video told the story of a major employer's settlement in the area and the impact their commercial manufacturing arm had on the community since the mid-40s. This year, we are exploring the military development side of things.
One of the styles we are using to tell the story is green screening. Because of all of the visual elements that we have at our disposal, we are once again shooting all of the interviews and the host's segments in front of our chroma key green background so we can insert video and still images in post.
Above is our setup for this type of shoot. Basically we set the camera about 6 feet or so in front of the subject and the subject 3-4 feet in front of the background to help reduce the visibility of any wrinkles in the background and to avoid shadows from the key lights. We then light the subject with a pair of soft boxes to provide soft, even lighting on both sides of their face. The soft boxes are elevated when the subject has glasses to help minimize reflections. We then add a back light to illuminate the subject's head and shoulders. Not only is this a good accent light, it also serves the purpose of adding definition between the subject and the background for a cleaner chroma key. Sometimes there is some spill over of the chroma key green onto the subject and adding a bastard amber gel to the back light will help reduce some of the green. Next we put two lights on the background to make it bright and as even as possible.
Once the subject is in place we will adjust the levels of the lights, making sure that we maintain a bright background without losing a decent exposure on the subject. One important thing to remember is to switch your camera to manual iris, otherwise you will end up with a dark subject.
By the way, even though it's not a great example, the above shot was taken with my new D200.
