Setting up a green screen to record footage of a subject that will be cut out and composited into another background has become commonplace these days. What is ultimately a pretty straightforward process, however, can be a difficult one to learn.
This video presented by Doug Guerra from B&H shows us some tips and techniques to help eliminate a lot of the common issues faced, such as colour spill, key fringing around our subject, and only partially removed backgrounds.
As is the case with pretty much anything you’ll put in front of your camera’s lens, the main ingredients are good lighting and a solid exposure. Large soft light sources will help to provide a more even spread of light across your background and prevent hotspots.
A good exposure, and a lower ISO will help to prevent other colours from creeping into your footage and polluting the background, making for an easier and cleaner key.
Where this may have been done with a handheld light meter in the past, as it is often done today, we are now presented with other options to help us ensure an even and consistent exposure on our backgrounds.
Mobile apps such as Green Screener (Android version) allow us to simply point our phone’s camera at a lit background, and easily see how the lights are falling, and where we may need to adjust things.
Just like shooting subjects on a white seamless, you’ll generally want to keep a good distance between the subject and the background.
This helps to not only prevent your subject from casting their own shadow onto the background, or your subject’s lights from causing hotspots on the background, but it also prevents light (and green colour) from spilling back onto your talent, and causing issues that can be difficult to correct.
Stopping the background lights from hitting your subject also means that you can light your subject separately with your background in mind, to help make the composite a little more believable.
Obviously, we all want to shoot our footage as correctly as we can. It helps to make our post workflow go as smoothly as possible. Sometimes, though, we’re not the ones shooting the footage and we end up stuck with whatever we’re given. Doug provides a few tips to help correct some common issues in post.
So, if you’ve been having green screen issues, or you’ve ever thought about giving it a try, either for stills or motion, have a watch of the video.
Fortunately, I get to shoot most of what I want to shoot on location and don’t need to deal with green screen all that often, but it’s definitely a useful technique to know for those times when there’s little other choice.
Do you have any other tips for shooting on green screen? Let us know in the comments.