The 69-year-old actor teamed up with Varma after two years for the action film, where he plays a gangster who eventually turns into a politician.
"In 'Department' its not just the 5D camera, several other advanced versions were also used... A unique experience!! Ram Gopal Varma has done just that in yet another pioneering effort in 'Department'," Bachchan posted on Twitter.
The film also stars Sanjay Dutt and Rana Daggubati in prominent roles and will hit theatres on May 18.
