How different film lenses affect how we perceive movies

There's a huge difference between a 25mm focal length and a 9mm focal length - and this video explains it

It's easy to underappreciate the nuances of filming techniques which go into your favourite movies.

The lens, for example, isn't just there to focus light; its focal length vastly affects the look and the composition of the shot, completely transforming how we perceive the subjects in the frame.

The focal length, in short, is the distance between the optical centre of the lens itself; and the film plane, which is where the image is focused onto the film - for digital, this is a piece of electronic equipment capturing light rays.

A video released by the University of North Carolina Wilmington's Film Studies department explores some of the ways focal length affects our perception of movies. Beginning with a 16mm camera, boasting a 25mm focal length; this look is considered the 'normal' zone, approximating the way our own eyes work in terms of depth of field, movement, and perspective.

Switching to a wide angle lens, with a 9mm focal length, greatly exaggerates the effects of perspective; while also increasing the apparent speed of movement by giving a much greater depth of field. 
 

A telephoto lens, on the other hand, boasts a 120mm focal length; shortening the effects of perspective, and giving a much narrower depth of field. That means movement through depth seems slower as the size of the subjects change gradually - perfect for those slow-mo hallways shots of girl gangs.

So with that information now kindly handed to you - time to go out there and make some movies!