Projectionist

The projectionist talked to us about a few different things; he told us about how a rough edit of a film is constantly being put together as clips come in to the editors. This contributes to a "first assembly reading" whereby a version of the film, usually an extended one, is shown. For instance, the one for Les Miserables was 4 hours long and had a 15 minute battle scene. After watching this, parts end up being removed and phased out.
Once the sequence has been decided upon, it is "lock picture" and from then, no further changes are made, apart from visual effects and music.
Films can be shot on film, but are usually are transferred to digital to be shown. This is mainly because of the difference in cost; it costs £2000 to deliver film in the 35mm medium and it can be easily damaged. It takes a skilled projectionist and hence it is an incredibly costly means. In contrast, digital is perfectly secure (no one can pirate from it) and the cost to deliver is only about £30; it does not require much skill to show, either.
The projectionist also spoke to us about 3D and high frame rate (HFR). He believed that 3D conversions "are a waste of time", and made the point that Disney paid millions to rerelease Monsters Inc in 3D recently, but it was a total failure at the box office and did not even come close to breaking even.
He believes that if the initial intent of a film is for it to be shown in 3D, for instance James Cameron's Avatar, then the film benefits from it. He felt that animations always worked well in 3D as they can be drawn in order to complement the 3D effect.
Although he had not actually experienced HFR, he noted that it can make it very expensive to shoot films; also, the result tends to be that for some, the film looks "too realistic" and does not have the typical film look.
The projectionist told us that 3D tends to add between 25 and 30% onto the budget of a film. The argument for and against the use of film depends primarily on if the money can be made back.