February Tech Talk: Green Screen

A green screen or chroma key is a backdrop used in film, television, and video production to add alternate backgrounds and effects. 

At PhillyCAM, we offer members access to a 28x15ft green screen in our Main Studio! Many members use the green screen to give their shows a more dynamic and polished look. Below are pro tips that every producer should know about using green screen.

Avoid live camera movement: Because the background won't move with the camera, having pans or zooms live on video breaks the illusion. Consider locking the cameras or doing camera movements offscreen while you've cut away to another angle.

Space is your friend: The more distance you can have between your subject and the green background, the less "spill" (or green glow) you'll have reflected onto your subject. One advantage to the size of PhillyCAM's green screen is that it offers coverage even when you bring your set out away from the backdrop.

Think about your background: You can use PhillyCAM built-in tools on set or create your backgrounds ahead of time in programs like Photoshop. Either way, you'll want to think about the perspective of each camera angle. For example, your close-up camera angles should show less of the overall background than your wide shot. You can even use warping/slant tools and simulated camera blur to create additional depth to your close-up backgrounds.

Do it in real-time: A big plus of using PhillyCAM's space is that our Tricaster allows the green screening to happen in real-time. This not only saves you time in editing and allows you to visualize your look on set, but it can also provide a higher quality key as the Tricaster has access to uncompressed video coming directly in vs the often heavily compressed video formats cameras usually use.

Don't wear green clothing!: The chroma keying software won't be able to tell your clothing from the background, which can lead to some hilarious (though usually unwanted) results with missing torsos, etc.

If you have any questions about our technical equipment or how to use it, please contact our tech team directly at techservices@phillycam.org or call 267- 639- 5481.