Duration of Trailer

Mainstream Hollywood trailers are usually around the 2.30 minutes and over. This is due to the competitiveness of that industry. With numerous films being released each year, the need for a director to show their film is vital for its success. This is why Hollywood trailers are traditionally over 2 and a half minutes to show off to audiences to longer.
E.g.
Iron Man 3 Trailer, 2.06 minutes
Jack the Giant Slayer Trailer, 2.31 minutes
Fast and Furious 6 Trailer, 3.22 minutes

However, smaller independent films have less competition. Due to the fact that they may be aimed at a small, narrow audience and even though competitive, fewer films will be released. Meaning that it is more likely that the film will be seen by the audience intended to see it.
E.g.
Tinker Tailor Soldier Spy Trailer, 1.21 minutes
Tyrannosaur Trailer, 1.53 minutes

The Paranormal Activity film series is where I've taken inspiration for my film. These films have become more and more successful There is debate whether the franchise has out stayed its welcome. Both of these can be supported by their opening weekend takings.
Paranormal activity 1 took in £3, 593, 762 (UK)
Paranormal activity 2 took in £3, 764, 722 (UK)
Paranormal activity 3 took in $52, 568, 183 (USA)
Paranormal activity 4 took in $29, 003, 866 (USA)

These figures can show that the franchise had an increase in popularity and then 'out stayed its welcome'
However, this increase in popularity supports my thought on trailer length within the 'Hollywood' industry and the 'Independent' film business. This is because as the popularity increases and the films become more and more 'Hollywood', the trailer length increases. For example;
Paranormal activity 1 trailer length - 1.03 minutes
Paranormal activity 2 trailer length - 1.13 minutes
Paranormal activity 3 trailer length - 1.37 minutes
Paranormal activity 4 trailer length - 2.11 minutes

For my trailer, as it is an independent film i have decided to have a short trailer. I have also decided to have a short trailer because I feel that some films are too revealing with their trailers by showing too much. I want my film to ask questions and not answer anything within the trailer to make the audience want to come and see it.