Conventions of a documentary

Voiceover
The voice over will usually be authorative, encouraging the audience to think they have particular knowledge on the subject and make people think they have the right opinions that should be listened to.

Real footage of events
All events that are represented need to be seen as being real to the audience and will go to great lengths to make the sure the footage is real and to be able to convince the audience that it is real.

Technicality of Realism
They use natrual light and sounding to make sure that the documentary is and seems like real life.

Interviews with experts
These are used to authenticate the views of the documentary or sometimes used to disaprove of the message the documentary is given however the documentary will then disaprove of them in some way.

Text
Text is used especially in documents to tell the audience who people are when they are speaking or to show where certain places are and to label things.

Sound
Sound may be used, espeically mood music. It is most likely to be used when the person is walking or looking at something to show some kind of emotion they are feeling.