Virtual Set

The virtual set is fast becoming a common means of television and film production. A virtual set uses green screen chromakeying to create a set or stage that isn't real, and in some cases could not be. An actor or talent stands in front of or on a green or blue stage and a piece of hardware or software called a chromakeyer like an Ultimatte removes the color and replaces it with an image generated by a computer. This image is called a virtual set, which can be designed by an in house designer, a company that specializes in virtual set design or you can buy virtual sets online.

A virtual set is ideal for situations where a real set is too expensive because of either space, location, or materials cost. Building a football stadium would be very expensive. Building a football stadium made of gold on the moon would be impossible, but not with a virtual set. A small stage covered with a green screen or blue screen and adequate lighting is all that's needed to put your talent anywhere your imagination wants to put them.

Chromakey

Sometimes Chromakeying for a virtual set is referred to as an art, because getting a seamless composite is less like a science and more like cooking; you need the right tools, the right ingredients, some imagination, and a lot of elbow grease. Traditionally the best way to chroma key for a virtual set is to light the background and the subject separately, this means that the backdrop gets a relatively even coverage of lighting, usually fluorescent, because most chromakeyers are susceptible to lighting variations and will give an uneven key. The talent is then lit to try and simulate the lighting environment of the virtual set. This can be difficult if the virtual set is dim because of the immense amount of light usually required to get an even key on the background and further exacerbated by the fact that the more light you put on the background, the more spill you get onto the talent's head and shoulders. An Ultimatte will fix up the spill, but not all keyers have this feature so special care must be taken when doing traditional chroma key lighting for a virtual set.