By Olivia Solon, Wired UK

Filmmaker and digital rights expert Caroline Campbell and visual artist Nina McGowan have teamed up to use customized drones to film unseen parts of Dublin city, including the inside of Facebook's and Google's headquarters.

Their film, Loitering Theatre, is part of the Science Gallery's Hack the City exhibition, which aims to "tweak and mash up Dublin's existing urban systems."

Campbell – who is a trained lawyer – and McGowan have been interested in drones since they saw a video of a Parrot quadrocopter from CES. Originally they were interested in using the drones purely as a filmmaking tool in order to take aerial shots without expensive helicopters and rigs. However, they very quickly realized that the drones they were using were only toys and that it was hard to turn them into a stable filming platform. They then found out about the Science Gallery's Hack the City initiative and were keen to use the drones to "democratize surveillance," as Campbell told Wired.co.uk.

"Some of the most prevalent alternative vantage points on our streets are security cameras, police helicopters and traffic cameras monitoring systems, which are controlled by our authorities and associated organizations," reads an explanation of the piece on the Science Gallery website. "However these different and unusual viewing points are rarely accessible to the individual citizen or in our control. Loitering Theatre focuses on the democratization of surveillance that drone flights afford."

Having crashed their first drone, the pair bought a Parrot AR.Drone 2.0 with the 720p camera that streams straight to a smartphone. They then took to the skies of Dublin over a six-week period to capture a new perspective of the city. In addition to exploring some of the empty houses left over from the property boom – ghost buildings – the duo paid a visit to the headquarters of Facebook and Google.

Keeping to public spaces, they flew the drone up alongside the buildings, allowing the camera to peer into the offices. Campbell explains: "Our argument is that Facebook has no expectation of privacy as their founder Mark Zuckerberg at one stage said privacy was no longer a social norm."

"The security guards were very aggressive. They made up lies about us crashing the drone into their windows and said we were disturbing their employees," said Campbell. "We feel that it is no more intrusive than something like Google Street View."

When they peered into the Google building, they managed to spy on a meeting taking place on one of the higher floors. Those inside the building spotted the drone, started filming it on their mobile phones and then closed the blinds.

"We are using the film to highlight the democratization of surveillance and to give a different view of the city by shifting it out of the human perspective of between 5 and 7 feet high," she said.

The film has proven to be of interest to Irish police, who visited the gallery where the film is being shown and requested that some of the footage looking over Mountjoy prison walls and the Irish President's house was removed.

You can view the Loitering Theatre video embedded in this post. Or visit the Science Gallery's Hack the City exhibition, on until Sept. 8, 2012.