It’s hard the green screen. It’s a different way of working – Rodrigo Santoro
Escapism has always been the forte of visual storytelling. The art of spinning an engaging yarn and weaving an intriguing fable through the medium of the moving image has kept audiences enthralled since the Lumiere brothers fired men into space in ‘A Trip To The Moon’.
Humanity is, as a species, a sucker for a good story, and the more involving it is, the more we’re captivated and enraptured by it.
With the advent of big-screen adventure and later small-screen escapades and shenanigans, we gradually lost our love of literature and instead sought our imaginary sojourns in the serials and films that we’ve come to depend on to lift us out of the doldrums that the humdrum toil of everyday life all too often leaves us wallowing in.
Even as they watched their audiences gasp in shock and shriek with delight as the rocketship hurtled toward the lunar surface, the Lumiere’s knew that time was a fickle mistress.
They were aware that their films, and the films of those that followed in their footsteps, would be limited by the technology available to their creators. While filmmakers could dream big, the ability to transfer their fantasies to the medium of film was often hampered and restricted by the equipment they could use to make their movies with.
Ingenuity, however, will always find a way to conquer the odds, and the invention of the green screen in the nineteen forties transformed the world of moving pictures. The story’s that writers and directors had always yearned to tell could now be told in a manner that would delight, and continue to amaze, moviegoers for decades.
The green screen, quite literally, changed the world.
What Is A Green Screen?
Green screen, or chroma key compositing as the more technically minded often refer to it, is a way of composition two separate layers of film, or images on top of each other to create a single image.
A bastion of special effects gurus everywhere and a director’s best friend, it allows television and filmmakers to create incredible flights of fancy without ever having to leave the studio.
And in case you’re wondering why it’s commonly called “green screen”, it’s because the process of superimposition that chroma key compositing is dependent on means that the background of whatever’s being filmed needs to green. Hence the name “green screen”.
While it’s an invaluable resource in the film-makers arsenal, to ensure that a green screen works the way it should, it needs to be properly lit. The technology that captures green screen images may have changed, but the rules governing the best way to use a green screen haven’t altered since it was first used.
It doesn’t matter how much money and time you pour into your project, without effective and proper use of lighting, just like Bruce the Shark, you’ll be dead in the water. So you’ll want to get the lighting right the first time. Which leads to the inevitable question – how do you light a green screen?
Lights, Camera, Action
Lighting a green screen isn’t a one-step process and isn’t as easy as just shining a couple of large spotlights at your screen and hoping for the best. That said, it can’t hurt to cross your fingers and say a couple of ‘Hail Mary’s’ while you’re setting your lighting and preparing your screen.
A little bit of faith goes a long way and whatever it takes to help you to get your set ready, is a necessary part of the journey. That said, let’s get back to the green screen.
Setting The Screen Up
Before you even think about lighting, the first thing you’ll need to do is set up your screen. It’s the canvas that you’re going to paint your project on, so you’re going to need to secure it and anchor it in place.
The green screen needs to be flat, tight, smooth, and wrinkle-free. Take your time, double-check it, and make sure it’s ready. When it is, you can move on to lighting.
Let There Be Light
Now it’s time to start lighting your screen. Position your lighting so that it creates a soft, continuous light that covers your screen evenly. It’s essential to avoid either hot spots, where the lighting is too bright, or shadow, where it’s either too dark or something is in the way and preventing the light from reaching the screen.
Once you’re comfortable that your screen is evenly lit, take a deep breath, relax and move on to the next step.
Never The Twain Shall Meet
Actors/ Performers and your green screen need to be lit separately. Establish the best way to light your actors away from the green screen and once you’ve figured out the best way to light your performers, it’s time to figure out the way to light the screen behind them.
Before you do though, make sure that none of your cast who are going to appear in the scene is wearing green. We know, it seems kind of obvious but it happens and when it does, it not only ruins your shot but it also wastes time and money and means that you’ll have to go for reshoots. Try to get it right the first time.
Step Down
The green screen is your background, so it’s going to need to be slightly darker than the lighting that you’re going to use for your actors/performers. It’s a balancing act, but it’s one that you’ll quickly get used to.
Just remember, that the lighting for the foreground (actors) has to be slightly brighter than the lighting you use in the background (green screen)
Shadow Is Your Enemy
If there is a shadow or shadows on the screen, it means your actors or performers are too close to the screen, and you’re going to need to increase the distance between them and it.
Figure out the distances you need to avoid any shadows appearing on the screen and move the cast and equipment accordingly. If there are shadows on the screen, they’re going to create all sorts of post-production headaches that you don’t, and won’t, need.
Go Wide
While it might seem counterintuitive, always crank the aperture of your camera wide open. When you’re filming with a green screen, a blurred background is okay.
If the screen is slightly out of focus, don’t worry – if there are marks on your screen, or it’s picked up a few wrinkles while you were lighting it properly, they’ll be eliminated by using a wide aperture shot.
Backlighting
Even though it isn’t strictly necessary anymore, as it can easily be fixed in post with a little software magic, it’s always beneficial to use backlighting as it’ll sharpen the edges and tone of your actors and background, give them both an additional sense of definition and help to separate them.
Check It And Check It Again
Before you start filming, check how everything looks through the camera lens. Make sure there are no hot spots or shadows and that both your cast and the green screen are adequately, and properly lit.
Then check it again. When you’re happy that everything looks right, and only when you’re absolutely happy that everything is lit as it should be, you’ll be ready to start filming your green screen scenes.
You’re Rolling
At the end of the day, it’s your vision that’s going to appear on the screen. It’s your story being told the way you see it.
Take as much, or as little, preparation time as you need to make sure that everything looks right before you start filming because time and film cost money and you don’t want to waste either of them.
The scene is lit, the cast is ready and it’s time to start rolling film. Three, two, one, action…
