In a first for ballet, Russia\'s legendary Mariinsky theatre will project every pirouette of its classic \"Swan Lake\" in 3D to cinema audiences around the world this week, a spokeswoman said on Tuesday. As the venerated troupe performs Tchaikovsky\'s ballet on stage in the northwestern city of Saint Petersburg on Thursday, 3D cameras will capture their moves and the images will be transmitted into cinemas in 50 different countries. Among those working on hi-tech screening is a company owned by James Cameron, the director of high-grossing 3D film drama \"Avatar\". The performance will start Thursday at 9:30 pm (1730 GMT) in the historic theatre, while a second audience will watch the show in 3D on its second stage, which opened last month. The performance, conducted by Mariinsky director Valery Gergiev, will in turn be beamed into 1,200 cinemas in 50 countries. \"It\'s the first time in the history of ballet that it has been presented like this,\" theatre spokeswoman Oksana Tokranova told AFP on Tuesday, saying that the quality of the 3D screening would be comparable with that of cinema blockbusters. \"It\'s a challenge because we have to transfer the magic of ballet into cinemas,\" one of the project\'s organisers, Ross MacGibbon, a former Royal Ballet dancer, told local television. Eight 3D cameras will film the performance in a multiple-camera system that aims to capture both closeups and different angles. The project is run by British group Glass Slipper Live Events, which worked with the late pop star Michael Jackson, as well as by US-based company, Cameron Pace, co-owned by film director Cameron. \"Ballet lovers should be able to appreciate the show, even if they are not able to travel to Saint Petersburg or to another city to see the ballet on tour,\" said Mariinsky director Gergiev.