Let’s kick off the beginners photography guide with one of the most important concepts for learning photography. Aperture.

OK, so what is aperture?

Aperture is the hole in your lens that lets light into the camera. The hole can get bigger or smaller, depending on how much light you need. The bigger the hole, the more light is let in, the smaller the hole, the less light.

That seems simple enough, wider aperture, more light. Got it. Is that all I need to know?

Actually, aperture also has another important job to do, it also controls the depth of field.

Depth of Field

Depth of field is the amount of an image that is in focus. A shallow depth of field means only part of the image is in focus, the rest is blurry.


Photographers use this effect when they want to get a blurry background (also called bokeh).

So if I want to make the lights on my Christmas tree blurry, I can use aperture to do this?

Yes that’s right, aperture is not the only thing that controls depth of field, but it is one of the factors.

OK, so how do I get blurry backgrounds?

You’ll need to open up the aperture, the wider the aperture, the stronger the effect.

How do I change my aperture?

You can change your aperture in manual mode or in aperture priority mode. In manual mode you control all the settings, in aperture priority mode, you control the aperture, and your camera controls everything else.

I recommend using aperture priority mode when you’re learning, so you can focus on aperture and let your camera worry about everything else.


How to Use Aperture Priority Mode

To change your camera to aperture priority mode, change the dial to A, or Av on Canon cameras.

Aperture Priority Mode

OK, I’m in Aperture Priority mode, now what?

Now we need to change the aperture. Aperture is measured by something called F numbers, for example F5.6, or F8. The smaller the F number, the bigger the aperture.

So F2.8 is a wide aperture, whilst F11 is a much smaller aperture.


You’ll need your camera manual to change your aperture. Sometimes aperture has its’ own dial. On some cameras, it shares a dial with shutter speed.

Time to practice. Get your camera and manual and practice changing your aperture. Don’t worry about taking photos, just make sure you can change the F number.

Once you know how to change your aperture, it’s time to practice.

To start off I recommend photographing something that doesn’t move, like a toy, so you can focus on your settings. Find a spot when plenty of light, such as near a window, and position your toy away from the background.

Don’t use a plain background, otherwise you won’t be able to tell how blurry it is.

No take photos of the object with different apertures. Notice how the background looks more blurry when using a wider aperture (lower F number).

Don’t worry if your aperture doesn’t open very far. Some lenses open up very wide, up to F1.2, whereas other lenses will only open to F5.6. Just open yours as wide as it will go.


Aperture Tests

If you don’t notice much difference in your images, try a few things to make the background blurrier:

  • Move closer to the object you are photographing
  • Move the object further away from the background
  • If you have a zoom lens, zoom in as far as it will go
  • Try using a lens with a longer focal length if you have one




If you have a zoom lens, you may notice that you can’t open your aperture as wide when it’s zoomed in. E.g. you can open to F4 when at 18mm, but when you zoom in to 55mm you can only open to 5.6.

Don’t worry, this is normal and happens with all zoom lenses (it’s to do with how the F number is calculated)

Keep practising with aperture priority mode. The more you use it, the easier it will get. Don’t forget to share your results with us on Instagram using hashtag #mamacameraclub.