An establishing shot in film establishes the context for a scene by showing the relationship between its important figures and objects.It is usually a long shot at the beginning of a scene indicating where, and sometimes when, the scene takes place. Estalishing shots usually use famous landmarks such as; NEW YORK CITY and the EIFFEL TOWER.
We've an establishing shot in our film in order to show the audience where exactly the character is. In this case, she is in a house in a 'posh' area. We then zoom in to a window implying that the character is in the room. There is then a match cut of the character inside the building.
(PUT ESTABLISHING SHOT OF OUR FILM HERE)
An establishing shot is usually short at about three seconds - however long enough for viewers to acknowledge the scene.
In the film :Wake in Fright it pans over the vast desert landscape of Australia, with unsettling music to convey that the desert is a dangerous place. it lasts for about half a minute. An establishing shot of this length would be wearisome if it is placed after the film had started, because by then the film should have been established.
(Wake in Fright Establishing shot)