How to choose use those blue and green backgrounds in your videos
February 8, 2011
Whether you’re doing a newscast, are video blogging or are doing still or video portraits where you want infinite variations for your backgrounds, Chroma-Key is the way to go. Here’s a very brief buying guide and mini-tutorial.
Even if you’ve never actually used one, if you’ve ever watched a TV newscast—especially weather reports—you’ve seen Chroma-Key backgrounds in action. A person stands in front of a blue or green background, called a Chroma-Key, but instead of seeing blue or green, you see a graphic background that could be a combination of another video or a wall, or a weather map, instead. The graphics are dropped in so it looks like the person in the foreground is actually standing in front of a wall or monitor.
Anyone who owns Adobe Premier Pro or Adobe Premier Elements and an HDSLR or Camcorder can achieve the same Chroma-Key effect by hanging a Chroma-Key colored backdrop behind the person or people you’re recording. While there are collapsible backgrounds (which are more expensive), both Lastolite and Westcott make 10x12-foot Chroma-Key muslin backdrops that are reasonably priced. You can buy a Lastolite blue or green backdrop for around $110, and a Westcott background in blue or green for $10-$20 more. Collapsable discs are generally smaller and more expensive. Go here to browse Adorama’s entire Chroma-Key background collection.
If you don’t have the creative know-how to create your own backgrounds, consider visiting Chromavault, which has a vast library of Chromakey background graphics (sample above) with a variety of themes that you can download for $20 apiece and create virtual sets.
How does it work?
You can use either blue or green—either one works equally well. Just make sure the people you’re taping aren’t wearing blue if you are using a blue background, or green if you’re using a green background. If they do, the background will show in their clothes!
Drape or tape the backdrop to a wall and turn any room into an instant studio! If you’re using Adobe Premier Pro, here’s how to drop in a background:
Take the clip that you plan to use as a background and place it on a video track on the timeline.
Then, take the clip with the blue or green screen in it and place it on the track directly above the background track.
Go Video Effects > Keying. You can select from a number of effects, including a blue screen and a green screen key. Choose the screen color you have and drag it on top of the video with the screen in it.
Finally, use the effect controls menu to fine-tune quality.
Be sure the scene is well lit to avoid telltale noise along the edges.
Whether you’re doing the weather, breaking news, a “talking head” video blog, or have other creative ideas, Chroma-Key affordably opens up endless possibilities.