How to Use Green Screen

About Chroma Key Technology

Chroma key technology is the technology which is used to create different backgrounds for the videos. Common example is of TV weatherman. The weatherman is shot standing in front of a green screen, which is substituted for the weather map background later. To accomplish this, you need a green background or the blue one. The background made of fabric can be bought from online or offline sources and can be used easily. For the whole process of chroma key, you need a computer system with sufficient hard drive space & memory and a video camcorder. You also need to have chroma key software. There are many software programs available in the market. Choose the one which is easiest to use.  

Chroma Key Software

Steps To Be Followed In Chroma Key Technology

1. Set up the shooting area with ample lighting. If one does not have a large room, the garage can also be used as a studio.
2. Do lighting with three lights. Lighting should be done evenly for blue or green screen backdrop by setting the lights at 45 degree angle from screen. The lights should be sufficiently far away so that they do not cause hot spots.

Green Screen Backdrop

3. Ensure that the subject is minimum 3 inch away from the screen. He/she should be lit with third light in a way so that no shadow is cast on the background.
4. Position the camcorder sufficiently far away from the subject to get the desired view. This depends upon whether it is a half body shot, a seated shot or a full body shot.
5. Film for 10 sec or little more of green screen background without the subject in the frame. This is to achieve a clean key with software later.
6. Move the subject at the desired location and begin shooting.  
7. When the shooting gets completed and the video is saved to the camcorder, the camcorder should be connected to the PC to load video onto it. Load the video and save it at a desired location on the PC.
8. Launch the software. Remove the green background from the video.
9. Choose a virtual video background to set in place of green background. On TV, weather maps are used as virtual backgrounds chosen from the PC.
10. Choose the output format for the new video generated. .AVI format is one of the best formats, as it is acceptable to almost all replay software.
11. Use editor to rearrange or delete scenes. Add special effects to the video. The video is ready now.

Green Screen Kit

It is recommended that you buy a green screen kit to have all equipments required in the process.