Put up blue screen, light properly, 3 or 4 point, ensure all
people/animation being recorded doesn't clash in colour, high quality
cancorders with 3 chips will be better to use for colour seperation, import
video into your editing app, move to the chromakeying section, select colour
to remove, remove it. Put the new background in a higher track, jobs done.
Simple explanation of a difficult task, but you gave very little info of
what you have to work with.
