In chroma key technique, lighting is the most important aspect to consider for bringing realism to the videos. The technique is simple to apply, but the lighting is tricky.
When lighting some scene in chroma key technique, there are some points which are needed to be kept in mind. Firstly, light will reflect back the screen color (green, blue or any other) on the actor. So, move the actor far from the screen as much as possible. Secondly, light the background evenly. For this, use lighting kit which offers diffused and even light. There should not be any hotspots or shadows on the screen.
The above points help you to create a clean chroma key, but this is only half of the total effort required. Another issue is to make the scene look real. For this, you need to carefully study the digital video background you have to use after removing green background. Consider these questions – Is it morning, afternoon, evening or night? Is it outdoor scene or indoor scene? What type of light is it – dark, soft or bright? What the mood of the scene is? Is the background moving? If it is moving, in which direction it moves? Is there any need to show rain effect or wind effect so as to blend the scene with the video background?
Lighting For Indoor
It is tricky to match the lighting of a video background with the scenes shot in an indoor studio using link
. If the video background, which has to be inserted in place of green background, was shot at some indoor place, it will be easy to match the lighting direction and color. Ensure that the fill & key lights are coming from the same direction as in the video background. Flag these lights to avoid spilling on the screen.
Lighting For Outdoor
If the video background, which has to be inserted in place of green background, was shot at some outdoor place, check the direction of the sun and type of sky. If the sun is bright, light the actor with small bright light which creates hard shadows. If it is cloudy sky, set up a diffused light and light the subject evenly. If it is partly cloudy sky, move small and narrow flag occasionally across the light so as to show that the clouds are passing. Place a fan which does not make sound blowing in the same direction as wind in the background.
Since the background to be inserted is video background and it will move, find whether there is any change in the light with the moving background. If it changes, then you need to change the studio lighting accordingly.