Depth of field (also called depth of focus) is how much front to back sharpness you have in your photos, and we've had a lot of people asking us to tell them more about how to control it. So here's a simple exercise you can do for yourselves to help you get experience.
All you need is a couple of lenses, a row of fence posts or railings, a tripod and some post-it notes. Then follow our instructions.
Depth of field is an important creative control so it's worth understanding how it works and how you can use it for better more interesting photos. And it doesn't matter what make of camera you're using, depth of field works the same on any DSLR camera.
If you'd like to ask us to make a film about an aspect of photography that's puzzling you, you can always send us a request on the Tell Us What You Want page on our site at www.photography... We can't promise to make your film but if we get enough requests for a particular thing we'll certainly look into a way of explaining it for you.