The green screen effect (also known as "chroma keying") is highly useful and pretty cool. Lighting a green screen is a royal pain in the neck, however. Luckily, B&H has released a video to help you navigate the process and pull off convincing shots.
Green screens are used all over the place, from TV broadcasts, to YouTube videos, to movies. When done well, they can be used to convincingly replace backgrounds, introduce special effects, or display information. It takes some work to properly light them, however. Doing so is crucial, as it's important that the screen represents as narrow a color range as possible to better enable its removal from the frame. This means having even lighting across the entire screen with no light or dark spots. This becomes trickier when one introduces the subject, as they must also be lit without affecting the established even lighting of the screen behind them. Furthermore, the appearance of the screen should be uniform, meaning creases, dust, tears, etc. should not be present. It's subtle, tricky work, but when it's done well, the effect is convincing and highly versatile. Check out the video above for a more in-depth explanation of the process and some great tips.
Do you use green screens in any of your work? Let us know your experience with them in the comments!
[via B&H]
I figured out a great trick last month... Stuck a green screen in front of my home theatre screen then projected a 60-minute grey background video on it with the projector. Cleanest key I've ever gotten.
Thanks for this. I was wondering if projecting through the screen would help solve the problem.
Can you explain how you did this more clearly? A diagram might help!
Interesting info, what app do you use on your iPhone to measure the green screen
https://itunes.apple.com/us/app/green-screener/id604935529?mt=8
No mention of colour subsampling - results will be much better if your camera supports 4:4:4 or 4:2:2. Lighting for head and shoulders shots is not that hard, it's when you need full length coverage that lighting gets really tricky.