There is a scene in Byzantium which features the starlings gathering late in the day, before they roost and fly across the sky as a CGI army of birds. As they dart through the air, they create a number of intimidating shapes and murmurations, terrorising the film’s stars and audiences alike.
Starring Saoirse Ronan, Gemma Arterton and Johnny Lee Miller, Byzantium tells the story of two mysterious women who seek refuge in a run-down coastal resort. Clara (Atherton) meets lonely Noel (Daniel Mays), who provides shelter in his deserted guesthouse, Byzantium.
Schoolgirl Eleanor (Ronan) befriends Frank (Caleb Landry Jones) and tells him their lethal secret – they were born 200 years ago and survive on human blood (although they are very different kinds of vampires, called soucriants, who can survive in the sunshine and are selective over who they kill). As knowledge of their secret spreads, their past catches up on them, with deathly consequences.
Bardsley, who worked as the lead animator for Prime Focus on this movie, says his team created a combination of wide exterior shots of these starlings. They also produced close-up shots of the starlings inside one of the caves on an island featured in the movie – providing an extra psychological edge to the scene.
One bird alone would not cause much trouble but when they fly together in large numbers, they strike fear straight into the hearts of the characters.
The large exterior shots were created using Massive and the internal shots were produced using Maya, before they were rendered by Guerrilla.
"The internal shots were very intense for the characters facing them and they posed a huge problem for us because we had to rig 800 characters in Maya. This is a lot of information to be processed and made to look believable, without the computer system breaking down," recalls Bardsley.
"Choreographing these birds in flight outside would also have been a logistical nightmare if we didn't have a master of Massive in post as our technical director – Martin Ruizi. He managed to design an original AI flock simulation system to fit in with Massive, which allowed us to do exactly what Neil Jordan (the director) wanted."
For the interior shots, Bardley's team started the process by creating three cycles of the starlings beating their wings, which needed to look slightly different, to create individuality for each bird.
These iterations were then processed to create hundreds of different characters in the scene, all flying with varying actions, despite acting in unison as a group.
Additionally, the rigging supervisor, Jakub Krompolc, also developed an in-house tool that allowed Bardsley's team to set a path for the birds to follow. Once this was designed, they determined how many birds should travel along it.
"The starlings could then be offset along the path and any one of the computerised flap cycles could be applied to them when necessary, making them all look authentic. Additionally, whe tool allowed the animators to alter the cycles and vary the speed for each bird."
To avoid too much repetition, Bardsley's team set a maximum of eight birds to follow each path at any one time, so a significant number of additional pathways needed to be manually built into the scene by the animators. However, Ruizi's tool helped hugely with creating a short-cut for this process.
"This flocking scene was a nicely contained sequence and a significant challenge both aesthetically and technically," adds Bardsley. "For those reasons, we had to pull our hair out at times. However, ultimately, these projects are the most rewarding when they prove to be successful."
His team used a wealth of real-life photographic material of birds flying through the sky, both as close-up shots and as big groups charging through the air. These videos proved to be essential reference material when it came to designing and creating the CGI shots.
"Fortunately, for us, there is plenty of excellent video material online of birds flying and starling murmurations. We closely studied the important aspects of the movement and then used our artistic skills to re-create these shots appropriately for the movie."
The end result is a hugely realistic, compelling vision of flying birds, as scary as anything seen in Hitchcock films, which would have been impossible to create using any other kind of special effects technique. The sequence is a great example of how to build a tense atmosphere, purely by using psychologically disturbing visuals.
Byzantium will be available on DVD and Blu-ray from Sep 11th.
Check out the trailer here: