To avoid the possibility of the screen being out of focus, and as a safeguard against the subject moving out of focus, decrease the aperture of the camera to bring about infinite – or near infinite – focus.
Shallow depth of field is really a no-no. Some simple things to keep in mind for any camera are to, first of all, remember that the background is a non-issue in the final, composed image. While there are many factors which can determine the ease by which a key is pulled (cameras, codecs, etc.) we’re going to keep things generic and easy. Alternatively, if clamps aren’t available, use something heavy and consistent to weigh the front of the screen down, pulling the wrinkles out straight down.Ĭameras play a large part when figuring out a keying shot. While there are expensive options from video stores, most hardware stores should carry inexpensive clamps that will do the trick just fine. To additionally avoid shadows from wrinkles and creases, clamp the screen thoroughly to the stands holding it up. Feel free to post which techniques have worked best for your shoots! There are a million ways to light screens and subjects, so agree or disagree with these pointers, and find which techniques work best for the scenarios you face.
Don’t forget regular lighting fundamentals, such as hair lights to add separation and perspective, but only if they suit the final scene. The rest of the frame can be dealt with later if it’s impossible to make perfect. The most important thing is that the area behind the subject is lit evenly. Use two large softbox lights – or other large soft light sources – and place each of them aimed toward the subject, but in front of them and on angle, so that each one cancels out the thrown shadow of the other. One cool trick is to use the subject lights (key and fill) to aid in lighting the screen if there aren’t enough lights to get the screen looking perfect on their own. If the camera and software see the blown out regions as white – or anything other than green – keying will be difficult. Work at making the light even and ensure no parts of it are blowing out (overly bright). There are lights designed to make lighting a screen easier, some even projecting a green light onto the green screen to force the evenness.