Choosing the appropriate focal length for the image you want to achieve is part of the creative process as well as the technical. There’s more to using focal lengths than just zooming in to make far off things come closer.
By using the right focal length for the job you can change the entire mood of a picture. You can make the viewer into a bystander observing the action from a distance or involve them and make it feel like they’re part of the scene themselves. (Check out our Photography Videos for more tips on the use of long lenses).
A short focal length will make a small space seem bigger and when put close to some foreground detail - add drama and a sense of depth to what could otherwise be a ‘flat’ picture. This is because they expand perspective.
A longer focal length will do the opposite because it'll compress perspective - drawing in and stacking things up behind one and other.
To demonstrate how focal lengths play with perspective - look at these pictures of Lorna. When I took them she didn’t move an inch.
Instead I started in close with a short focal length, then extended it and moved myself back each time so Lorna would be about the same size in each composition.
Notice how big Lorna's hands are in the 12mm image. It's because short (or wide) focal lengths expand perspective and make things closer to the lens bigger. And there's not a tree in sight - though I promise you they're there.
You can't see them because the short lens has pushed them away so much they're small enough to hide behind Lorna's head! Perspective has expanded.
As I moved back and extended the focal length to 24mm - they start to poke out behind her. I promise she didn’t move and I haven't shifted round to change the angle I'm shooting from either!
They’ve appeared because the longer length of lens is drawing the background up behind her - enlarging it and starting to compress perspective. As I keep moving back and extending the focal length each time the trees sneak in closer and closer.
Try this as an exercise for yourself and you’ll see what I mean.
So where and when would you use this focal length / perspective effect? Well pretty much anywhere your imagination takes you.
How about using
- A middle focal length (70mm ish) to get a natural looking portrait.
- A short 12mm down low to make your viewer feel they're actually in the sea.
- A long lens (200mm ish) to bring the other side of the valley in closer as a background to a wedding couple.
In my next photography tip I’ll show you how to use varying focal lengths when photographing landscapes. Because contrary to popular belief - Landscape Photography isn’t just the domain of short wide angle lenses.
All of this and more is covered in our camera lenses course Lenses Exposed (which is only £5.99). If you’d like to come and get some hands on experience with me and get to grips with focal lengths as a creative tool then a One to One photography Course would be perfect.