Green Screen Tips
Some software packages provide dedicated green and blue screen effects which may require the screen to be a very specific colour. If these effects don't work, use the more general and forgiving chroma key effect.
In most studios there will be some variation in the screen colour, no matter how hard you try to make it consistent. When selecting the key colour, try to select a part of the screen which best represents the overall colour.
Key parameters to adjust include similarity and blending. Experiment with these to see how they work. You will almost always have to adjust these to get an acceptable effect.
Make sure anyone appearing in your video is aware that they cannot wear green (or blue if you're using a bluescreen). You also need to avoid green (or blue) props and other objects. Watch out for logos and symbols on people's clothing — these may be small enough that nobody notices them while shooting, but after adding the key they become horribly obvious holes in the person's body.
As well as avoiding green or blue, you will probably notice that some colours and shades work better than others. For example, dark coloured clothes may create more of a green rim around foreground objects than light colours. You should spend some time experimenting with lots of different colours.
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