If you do a lot of chroma key<\/strong> work than you are probably very familiar with how difficult the entire process can be. From lighting the background to minimizing spill, there are a million different things to think about (and mess up) along the way.<\/p>\n However, the difficulties associated with modern chroma keying<\/strong> fail to compare to that of keying in the pre-computer world. Using techniques like contrast mattes and sodium vapor lights, filmmakers of years past had even more difficulties pulling\u00a0good chroma keys.<\/p>\n In the following video Tom Scott explains how filmmakers and TV professionals achieved chroma keys in the pre-computer age:<\/em><\/p>\n