Generally, the screen is the viewer’s window into the film’s world and it behaves like human eyes: you see one image at a time. But film can be a lot more flexible than that. You can, in fact, be more creative and see more than one image at the same time, each battling for your attention or complementing one another. The most traditional reason to have two images side by side is for telephone conversations so you can see both people talking and, more crucially, their reaction to what they’re hearing.

Look at any movie or television show, from any period, and you’ll see that the editing never stays on the same shot for too long. In fact, you may feel that some do overstay their welcome and you get impatient for the camera to move on to something else. Changing shots doesn’t mean changing scenes: when done right, cutting to different angles keeps the story interesting and the pace flowing. It also makes it easier to use a better take, or to cut to the scenery that is being described in the current shot, while still hearing the narrator talk about the location.

There’s one element that makes it obvious you’re watching an amateur movie: the audio. Although nearly all camcorders or video recording devices capture sound as well as images, the quality is often very poor. Even HD camcorders that produce vibrant, high-quality clips are often let down by the low quality of the on-board mic.

The dolly zoom effect is very recognizable: the subject in the foreground stays motionless, but the background appears to change and zoom out so you can see more of it. To create this effect, you need to move the camera back as you zoom into your subject. The speed of the tracking back and zooming in must be the same for the subject’s size to remain the same. The effect works very well, but is very difficult to replicate with a consumer camera since the zoom controls on such devices are far from precise.