Fixing halo and creases in a greenscreen curtain?
 

Hi, I'm a student at a high school studio, and we've been having a lot of problems recently lighting our greenscreen curtain. We use a real-time keyer (as part of the GlobeCaster system) and find that we keep getting a slight halo-effect around the talent. We've tried increasing the backlight and changing our entire lighting system in order to better separate the talent from the background, but none if it really seems to be working. In addition to this problem, our curtain creases and of course those creases cause shadows so our screen is very far from being evenly lit. Do any of you have any suggestions on how to fix either of these problems? Your replies are definitely well appreciated! Thank you!!

If you can get the curtain to stay tight to eliminate the creases... that would solve one problem. Weights at the bottom and tethering the curtain to the left and right maybe??

seperating your subject from the screen is very important. the more distance the better.

I typically use flourescents to light a cyclorama or green screen since its a soft light that already gives off a greenish cast.

You already know what needs to be done, you just gotta do it!

You can also add a rim light to your subject (above and behind) making a rim of light around them that will help separate them from the background. If you use a very light magenta or CTO, it'll help even farther without looking totally out of place (depending on what they're being composited into.

If you increase the distance to the screen, enough, you can also move the camera farther away. This will allow you to zoom in a bit, and open up the iris (exposure) as far as it will go. If you get too much light, add a neutral density filter to bring the light levels back under control. This will blow the background out of focus and smooth out the wrinkles a bit for you :)