A team of imaging experts, scientists and historians will set sail for the Titanic on Friday to gather the most detailed photographic record ever made of the wreck.

The BBC has had exclusive access to expedition members here in the US city of Providence, Rhode Island, as they make preparations to leave port.

They'll be using state of the art technology to scan every nook and cranny of the famous liner to gain new insights into its sinking.

This will be the first commercial mission to Titanic since last year's OceanGate tragedy . Five men died while trying to visit the lost ship in a novel submersible.

A joint memorial service will be held at sea in the coming days for them and the 1,500 passengers and crew who went down with Titanic in 1912.

The new expedition is being mounted by the US company that has sole salvage rights and which to date has brought up some 5,500 objects from the wreck.

But this latest visit is purely a reconnaissance mission, says RMS Titanic Inc, based in Atlanta, Georgia.

Two robotic vehicles will dive to the ocean bottom to capture millions of high-resolution photographs and to make a 3D model of all the debris.

"We want to see the wreck with a clarity and precision that's never before been achieved," explained co-expedition lead David Gallo.