Chroma key is the technology used to create a different background in a video. A common example of a chroma key is that of the meteorologist on television.
The weather on TV is recorded with the meteorologist standing in front of a blue or green screen. A time map then replaces the blue or green background. To get this effect you will need a blue or green background, a video camera, and a computer with lots of memory and hard drive space. You will also need software like Adobe's Ultra CS3 or Adobe's Premiere Pro. Once you have them follow the steps below carefully.
Steps
Step 1. Set the shooting area with adequate lighting for the camera
If you don't have a large room, the garage will be fine.
Step 2. Arrange the three-light lighting
You need to illuminate the blue or green background evenly with the lights set at a 45 ° angle from the screen. The lights should be far enough away so as not to cause hot spots.
Step 3. Make sure the subject or talent, as the subject is called, is a minimum of three meters from the screen
Your talent must be illuminated by the third light so that there is no shadow cast in the background.
Step 4. Position the camera far enough away from the talent to get the desired view:
whole body, waist up or seated.
Step 5. Film ten seconds or more of the blue / green background without the talent in the box
This will be used later to get a "clean" key with the software.
Step 6. Move your talent to the desired location and start shooting
If you're going to use live audio, attach a good lavalier mic to the talent's clothes, far enough away so your breath isn't caught by the mic.
Step 7. Start shooting the video taking care to shoot a few seconds beyond where you will be with the editing
Step 8. After capturing the video on the camera, connect it to the PC via a fire-wire connection
Attention: With a DVD camcorder, the video must be transferred to the hard drive in another way.
Step 9. Switch the camera to VTR or VCR mode
Step 10. Open the software
Step 11. Advance the cutscene to the point where you have the blue / green screen without the talent
Ultra allows you to work automatically or manually. In general, with adequate lighting, the automatic works well.
Step 12. Select the static scene or virtual set as the background where you want the talent to appear
On the TV they are using the weather maps as wallpaper from the PC.
Step 13. Select the compression or Codec to use
This is because video from a camcorder will create a large file. A rough rule of thumb is that ten minutes of video equals 2GB of hard drive space. The codec (compression-decompression) used will reduce the file size depending on the type of codec used. Remember that nothing is free: when you compress, something is lost and quality is reduced, but lossless codecs are available.
Step 14. Select the output format you want to use, such as the.avi format which is accepted by most of the playback software
Step 15. Let the software render the video
This may take some time depending on the length of the video and the speed of your computer and the resolution you have selected.
Step 16. Save the result and you are done
Step 17. Now you can take the video and use it with an editor like Pinnacle Studio, Adobe Premiere, or Premiere Elements
You can use Microsoft Movie-maker which is part of Windows but has very basic capabilities.
- In the editor, you can delete or change the order of the scenes as you like.
-
You can also add background audio as well as titles and credits. Special effects software is available that will allow you to create things like lightning, explosions, and other special effects.
Use a Green Screen Step 18 Step 18. Know that Chroma key allows you to let your imagination run wild
In an afternoon, it is possible to be in front of the Sphinx, the Taj Mahal and on a beach in the south of France, all without leaving the room where you have your computer.
