Focal length is how we describe the magnification of your lens and it's described in millimetres. Some have fixed lengths and others can be 'zoomed' in and out as you change the focal length.

If you zoom your lens you're probably trying to get something that's a long way off to come nearer. But 'zooming' changes more than just your focal length.

As well as magnifying, focal length changes three other things as well, perspective, depth of field and field of view. Each of these have a dramatic impact on the way your images look, what's included and what's not and what's sharp and what's soft.

Different focal lengths change the way the viewer feels about a photo too. In Using a Short Lens we showed you how a wide angle or short lens has a very close in intimate feel to it. Long lenses have a more isolated or by-stander feel to them and it's all achieved by altering your focal length.

Once you've been shown how to exploit this and invested a bit of time practising - you'll have taken a huge leap forward in controlling the way your pictures look.

Do you feel you've got to grips with Focal Length? If the answer isn't yes - then have a look at the Masterclass in Photography short course that I offer... I'll explain it simply and clearly, I promise!

• I Mess Up Salsibury Catherdral Photo Shoot - EP31
• Photographing A Landscape Landmark PT2 - EP30
• Photographing A Landscape Landmark PT1 - EP29
• Exposure Bracketing Explained - EP28
• Woodland Photography with Gary Gough - EP27