Using a Green Screen and Chroma Key in Video Production

Posted on: June 15, 2023

Using a Green Screen and Chroma Key in Video Production

You’ve probably heard of and seen a green screen before but you may not know what incredible things you can do with it and how exactly it works.

You’ve probably heard of and seen a green screen before but you may not know what incredible things you can do with it and how exactly it works. Well you’ve come to the right place. In today’s tutorial we’re going to cover all the basics: what a green screen is and why it’s used in video production, which equipment you need to get started and some tips on setting up and working with a green screen. Once you have the basic understanding of a green screen, you’ll see that it’s a simple tool that can elevate your video projects to the next level.

What is a Green Screen and Chroma Key?

So what exactly is a green screen? In simplest terms, it’s a blank green backdrop used for filming that is later replaced with a different image or footage during post-production. This process is called “chroma keying”, and it allows filmmakers to create incredible in-camera special effects or composite shots without having to build intricate physical sets. The bigger the budget the bigger the green screen can get. You’ll see behind the scenes footage of huge action scenes in a movie being filmed on green screen sets. Today we’ll just be focusing on smaller scale green screen background set ups. But the main concept remains the same: green goes away, more detailed background comes in.

How Does a Green Screen Work?

Essentially, a green screen is a solid color background that you can easily remove out of a video using special video editing software. By filming in front of a green screen, an editor can then seamlessly layer in any background they desire during the video editing process. Of course, there’s a bit more to it than just plopping a green sheet in the background of your photography and hitting record. Lighting, camera placement, and precise programming all play crucial roles in creating a convincing effect.

Does it have to be green?

The short answer is no, you could use any color in the same way. But green (and sometimes blue) is easiest color to use for a number of reasons. First, green is an easier color to avoid having on your subject, such as in their clothing or skin tone. You may have seen videos of a weather person having their clothing become part of the map. That’s because they wore the same color. Avoid doing that. Also, a bright green color lends to an easier key in the editing process for some technical reasons that we don’t have to go into.

The Benefits of Using a Green Screen

The use of green screens in video production allows filmmakers to create scenes that would otherwise be too expensive or time-consuming to execute. Rather than building an entire set or traveling to a remote location, a green screen studio can be set up anywhere, with any backdrop imaginable added in post-production. It can also effectively be used to aid in special effects production. Let’s say you want to have your famous comic book hero Weird Doctor have sparks fly out of his head and then disappear. Film the scene with a green screen makes this much easier to accomplish. Using a green screen is a cost-effective and time-saving solution that has revolutionized the industry.

How to Use a Green Screen in Your Studio

Now that I’ve successfully convinced you to start using a green screen, it seems the responsible thing to tell you how to use the dang thing. It’s not quite as simple as hanging up a green sheet in your studio. That being said, your first step is to…

Hang up your green screen

Depending on what you’re shooting, the size of your green screen should at least allow your subject to fit inside the color. If they are raising their arms or another motion and going past the green screen, you’re going to want to use a bigger backdrop or change the actions. Make sure your screen is tight and has no wrinkles or dirty marks that might show up on camera.

Light your green screen

Have you ever watched a green screen video where the subject’s face seems to spill into the background? Or maybe you’ve seen a video where the subject is almost transparent, like a ghostly apparition in motion. These are the telltale signs of incorrect lighting for green screen videos. Invest in some good quality lighting equipment – your video (and viewers) will thank you! And trust me, you don’t want your audience to be distracted by unflattering shadows or weird green tinges – focus on the content, not the lighting mishaps.

Light the screen separately

You’ll have to approach these shots differently than when you shoot a normal 3-point lighting scene. First focus on lighting your green screen evenly. If you’re in a studio and not outside in natural lighting, set up your lights on both sides so you don’t get shadows or darker spots. If you can’t afford to buy or rent expensive equipment, you can grab some florescent clip lights from a hardware store, you just might need to pay closer attention to how even your lighting is.

Prepare your subject

Once you’re happy with how your green screen backdrop looks, it’s time to move on to getting your actors looking their best (or whatever you’ve got in front of your green screen).

The distance between your subject and the green screen

The more distance you can give between your subject and the green screen the better. If they are too close it will be difficult to make it look right when you replace the background. It depends on the project and how big your frame is so it’ difficult to give an exact measured distance but for an interview type set up 8 feet is probably good. Bigger scene, bigger distance.

Light your subject

You’ve got your background lit, now you can light your subject with a key and fill lighting technique. You may want to keep in mind what your background will be to make sure lighting sources match. For example, if in your background scene the sun is shining from up right, you’re going to want to light your actor to give the same effect.

Don’t let them wear green

Like we mentioned before, if your subject has green on their outfit, it will bleed over into the final background image, so make sure to check them out for any green. Also, before you start filming you should take a close look at the image being picked up from the camera and make sure no green is being reflected on to your subject from the green screen. This can happen when your subject is too close to the green screen or if they have any reflective jewelry or something of that nature. It’s important to catch these little things before they cause a problem for your post-production team.

Editing with Green Screen

Now that you have your raw green screen footage you it’s time to create the scene you always envisioned. First, import your footage or image into editing software that supports green screen editing features. Whether you use mac or windows you can find some video editor software to use. This can range from free video maker software like iMovie to professional ones like Adobe Premiere Pro.  Use the chroma key effect Ultra Key tool to remove the green screen and replace it with the background footage you’d like to use in your project. And you’re done! Just kidding. You’re probably going to want to make some tweaks to your project so it doesn’t immediately scream “GREEN SCREEN”. Here are a few tips.

Tips for editing with a green screen video

1) Add your raw footage into your full project before using chroma key and correcting your background. This’ll save time. Once you lock in your scene you can then start keying out the green and color correct as you like.  No point in spending a ton of time on fixing something that you’ll remove later.

2) You’ll most likely want to make adjustments to your background to make it look better. There are specific tools you can use in your editing software to get your footage to match more exact so play around with it until you like what you see.  Things like playing with the background focus, adding shadows or lighting effects.

Create a New World with Green Screen Video

Using a green screen for your video production can be an excellent way to save time and money while generating your creative content. You can make it easy on yourself by following the simple steps we’ve outlined today. Remember, proper lighting is crucial for achieving optimal results and make sure your actor isn’t wearing a green tie!  If you’re ever unsure of anything or need help with a project feel free to reach out to BLARE Media. We have plenty of experience and are pros at working with green screen production. Get in touch with our team today and let us take the wheel for you!