3 Common Blue Screen Problems During Production

Blue screens problems are issues that a filmmaker needs to overcome when using the chroma key effect. Chroma keying is used to replace a solid color in a shot with a different image. With this effect, you can heavily stylize the look of your work, or you can be transported to far away places that you can’t really go to. It is a special effect, and if it’s not properly executed in production, then you’re going to run into a lot of trouble in the editing room. Here are the 3 most common blue screen problems.

1. Improper Lighting

The biggest blue screen problem during production is that it was not properly lit. Chroma keying works by isolating a specific color, which is then keyed out. If the blue screen is poorly lit, then the camera is going to pick up several shades of blue instead of one distinct and uniform color. This can be a real pain because every shade will need to be individually keyed out. It creates a lot of work for the editor and it risks having part of an actor, set piece or prop being keyed out along with a dark shade of blue.

You need to devote some of your lights to just lighting the blue screen. The lighting should be flat and consistent with everything at the same exposure level. You need to isolate these lights from hitting anything else on the set. You also need to keep your set lights from spilling onto your blue screen as well.

2. Dirty Blue Screen

Remember that chroma key works best when the blue screen is a consistent and even color. A dirty blue screen can be picked up by the camera, which would then make your screen more than one color If the blue screen is dirty enough, it can cause keying problems in post production. If you own a blue screen, then take care of it, and if you’re renting one, make sure you thoroughly inspect it before the shoot.

3. Blue Objects on Set

If you’re working with a blue screen, then your actors cannot be wearing blue and the props can’t be blue as well. if something in the frame is the same color as the blue screen, then it will be keyed out along with it. The effect doe not distinguish objects, only colors. Be prepared and plan out the colors of your frame accordingly.

Keep an eye out of for reflective surfaces in your set pieces. These could pick up a blue refection that you might not immediately notice. These reflections will create unwanted keying. If you’re on top of your game, then you can avoid these problems and have a smooth effect.