Green Screen: Definition, Functions, How It Works, and Tips

If you've ever watched a modern Blockbuster, you know the green screen. Green screen is a backdrop or background with a green background that is used to make photos and videos. Previously, green screens were blue when Larry Butler first used the color keys in 1940's The Thief of Baghdad, which won him an Oscar. To learn more, let's look at the meaning, function and operation of a green screen in this article.

What are Green Screens?

A green screen is a large backdrop or green background that is placed over a background or image object. After the production process is complete, this background will later be modified using CGI technology or computer graphics.

The green screen application was first used by George Albert Smith in 1898. Initially, the cloth chosen was black to remove objects. Also, in 1903, green screen applications became very popular. That's because the movie The Great Train Robbery painted the windows of the train black to enhance the scenic view of the train passing by. This is of course the beginning of the popularity of green screens in their application to support film visual effects.

Green Screen function

The green screen acts as a background so you can add CGI or special effects to your video. This is used to change the background color in edited special effects movies. The process of changing the background color from green to CGI is called chrome keying.

How Green Screens Work

Conceptually, the operation of the green screen looks very simple. The filmmaker captures the video object with a backdrop that previously had a green background. Also, merging or faking background objects is done with video editing tools or software.

When these images are combined, CGI effects are added to the background as needed. It is important to ensure that the subject and background are sufficiently and evenly exposed so that no shadows appear in the image. Apart from that, you can change the appearance of the video background and add other visual effects as needed. Even though it looks very simple, in order for the chrome key to produce high-quality videos, you need competent skills in the process.

Tips for Using Green Screens

Here are some tips to help you maximize the use of green screens in film production.

1. Note the Lighting Level

Pay attention to the light level, because the light level has a big influence on the successful use of the green screen. Exposure should be adjusted evenly in both the foreground and background.

2. Don't Ignore Imagine

The green background must appear solid with the color intact for the keying process to work. Thus, the subject must be several meters in front of the screen during the shooting process, and must be illuminated by three-point lighting.

3. Deep of Field

The depth of field of the foreground and background must match, otherwise the resulting image composition will not match the human eye and will look odd.

4. Use a tripod to stay stable

For your green screen to work, your camera needs to stay steady and sharp. Shaky camera in the background can see the stability of the background.

5. Avoid Clothing or Props

Green clothes or props can damage the green screen, so make sure the player's clothes are not green.