Sunday, December 21, 2008

Green Screen Technique For Video Production

Here is a quick response to a question a reader asked the other day about how to green screen. He wondered how far the on-camera person should be from the green background. He said he was very frustrated because he had searched for an answer and everyone said something different. There was no consensus so he was confused. I explained that the reason no one seemed to agree is because the proper distance between the background and the on-camera talent is entirely dependent on the particular situation under which you are videotaping.

When you're making a video using green screen technique, how far away from the green background should your on-camera person be? A reader asked this the other day and said he was very frustrated because he had searched for an answer and everyone said something different. There was no consensus so he was confused.

I explained that the reason no one seemed to agree is because the proper distance between the background and the on-camera talent is entirely dependent on the particular situation under which you are videotaping.

On a technical level, the distance is totally irrelevant. What matters is that the green background is an even color. No variations. Shadows are one of the chief problems that cause variations in color. The darker color of the shadow will cause the green screen effect to be uneven.

If the on-camera person is standing very close to the background, chances are her shadow will fall on the background. But if the on-camera person were twenty feet from the background, the same shadow would fall harmlessly on the floor, which is cropped out of the picture.

Problem is, most people do not have the luxury of that much room.

In an ideal situation, most professional videographers would place the on-camera talent at least five or ten feet from the background. This gives the talent a little breathing room and helps ensure an even background.

However, when I took a tour of ABC news studios, I saw them videotape a news update and the anchor person was smashed up against the wall. They shot the news update from her office, which was tiny. It looked great on the air. I could barely tell it was a green screen. It looked real!

The lighting in her office was extremely diffused so there were no shadows. The green behind her was homogenous in color which gave a beautiful green screen effect.

So if you have some room to play with, go for a distance of about ten feet. If you don't have the room, do not worry about it. Just make sure your lighting is diffused so the shadows will be minimal or non existent.

If you have a video production question you'd like answered, drop me a line a videoproductiontips@gmail.com I'd love to hear from you!