Guitar Hero Live fills its stadiums using 400 actors and a two ton robot camera from The Hobbit

When it wasn't filming hobbits, wizards and dwarves in questionably fragmented fantasy prequels, a certain two-ton camera was used to capture the live-action concerts of Guitar Hero Live. The giant robot was previously used to film two shots at once, thus helping The Hobbit director Peter Jackson seamlessly combine them into one complete scene.

In the latest issue of Edge, Freestyle Games, the developer helming Guitar Hero's comeback title, reveals how it used a similar technique, filming its real-life crowd in front of green screen while capturing both positive and negative reactions. By taping both responses at the same time, the studio is able to flit between the two at will depending on the radness/bogusness of your in-game performance. So that's a dynamic live audience to keep you on your toes in the main campaign alongside the separate Guitar Hero Live GHTV service, which uses official music videos to test your strumming skills.

Sound complicated? You bet your hipster wardrobe it is! Freestyle realised the uber-expensive camera wasn't able to film both the crowd and the band at the same time, so the band's pre-show scenes were written, rehearsed and shot separately.

In order to capture the look and feel of a 5,000-strong crowd, a group of 400 extras were filmed giving good and bad reactions in one position, before changing their clothes and repeating the same process in a different order four or five rows back. This process was repeated over and over again until the illusion of a big gig audience was created (with a little help from some CG).

The latest issue of Edge, with Guitar Hero Live on the cover, is out now. Want to know more? Of course you do. You can buy a copyhereorsubscribeto future issues.