(Cover) - EN Movies - Rob Marshall has branded his decision to shoot Pirates of Caribbean: On Stranger Tides in 3D "ridiculously stupid".

The director insisted on filming the latest instalment of the franchise in 3D rather than convert 2D footage once filming had finished - a process used in several Hollywood blockbusters like last year's Clash of the Titans and the forthcoming final Harry Potter movie.

However, while delighted with the end result, Rob conceded that using the bulky 3D cameras on location was a headache.

"I think we were very much pioneers in a way because we brought this very delicate 3D equipment into really remote locations, which maybe, in retrospect, was ridiculously stupid but because it was hard," he told Cover Media. "For me, it was worth it to shoot in real 3D not in 2D and then convert it. You really feel like you're there, so it was tricky but it was worth every bit of it."

Despite the challenges, Rob believes the film had to be shot in 3D, adding: "In terms of the 3D, we had a choice at the beginning either to do it as 3D. I'm sort of from the school that not every movie should be 3D, I think the material has to lend itself to it. This just made sense It was challenging."

While converting the film into 3D is a cheaper process than filming in the new format, critics claim that it's inferior to movies shot in 3D. It's an allegation that is backed by James Cameron, director of the hugely successful and innovative sci-fi blockbuster Avatar. (C) Cover Media