New video has come to light of the Costa Concordia's captain on the bridge in the minutes after the ship hit a rock off the Italian island of Giglio.
Seventeen people died and 15 are still missing after the ship capsized when an underwater reef tore a hole in its hull as it passed just 150m from the shore.
Captain Francesco Schettino, 52, has been accused of altering the vessel's course so he could show off to friends and crew.
He is currently under investigation for multiple manslaughter, causing a shipwreck and abandoning the Costa Concordia when passengers were still on board.
The 10 minutes of film, screened on Italian TV news channels, shows for the first time the reaction of the ship's captain and crew as they dealt with the situation after several water-tight compartments on the 114,500-ton ship were breached.
In the footage, a man identified as Mr Schettino can be seen speaking on the telephone in the half light of the bridge, illuminated only by emergency lights after the power failed on the liner with more than 4,000 passengers and crew on board.
At one point in the film, almost 45 minutes after the ship had hit the rocks, an officer is heard shouting: "Captain, the passengers are starting to get into the lifeboats on their own."
Mr Schettino appears to reply: "Whatever... whatever... OK."
Despite the growing tilt of the ship , which later led to difficulty in lowering lifeboats, Mr Schettino still refused to give the order to abandon ship for a further 15 minutes.
Prosecutors want to know why he waited more than an hour before ordering the ship to be abandoned off the coast of the island of Giglio.
They are also questioning why he made a series of telephone calls to the ship's owners, Costa Cruises, at their control room in Genoa and why he left the stricken ship when passengers and crew were still waiting to be saved.
Chief investigator Francesco Verusio immediately ordered TV station TG5 to hand over the footage.
He said: ''I didn't even know this film existed. None of the officers questioned mentioned it. I have asked for it and it will form part of the inquiry.''
The film shows several people on the bridge of the passenger liner and officials believe these include the Concordia's purser and restaurant manager who were invited there by Mr Schettino.
Captain Schettino is currently under house arrest near Naples.