How to take a beautiful portrait: Develop your passion for Photography

As a professional photographer, one of the questions I get asked the most is ‘how do I make a portrait with a beautiful blurred background?’

There’s lots of things to think about when taking a picture, but the short answer is: Aperture.

Aperture is one of the settings that has the biggest impact on a photo, because it controls how much light hits your camera’s sensor, but also how much of the scene is in focus.

What is Aperture then? The easiest definition for aperture is to say that it’s the opening of your lens. If you take a close look at your camera’s lens, you should see something like a hole in the middle and if you move the ring, the hole will get bigger or smaller. This adjustable “hole” is also called the diaphragm.

The best way to understand aperture is to think of it as the pupil of an eye. In low light conditions, the pupil is wider, letting in as much light as possible. When there’s too much light, like direct sunlight, it shrinks to compensate for the amount of light (especially cat’s pupils!) In photography, the lens of your camera works just like this.

Let’s follow this analogy. Would you use a wide or narrow aperture to photograph a darker scene like an evening party? If you enter any dark place, your pupil widens up.

The same goes for the camera. As you change the aperture, it allows more or less light onto the sensor. This depends on the situation and the scene being photographed. So, a smaller aperture allows less light in and a larger aperture allows more light in.

In photography, the aperture size is measured using something called the f-stop scale. On your digital camera, you’ll see ‘f/’ followed by a number. This f-number denotes how wide or narrow the aperture is.
The scale is as follows: f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22.

Now comes the tricky bit, I know it can be confusing, but please bear with me. A wide aperture - so lots of light - is associated with a small number like f1.8 or f2. A narrow aperture - so little light coming in - is associated with big numbers like f16 or f22.

To recap, aperture controls how much light hits your camera’s sensor. It also controls how much of the scene is in focus. This is called depth of field (DOF). A wide DOF means that more of the scene is in focus. A shallow DOF means only some of the scene is in focus.

If you want to have everything in focus, you would use a small aperture like f16 or above.

On the other hand, if you are taking a portrait, you would probably want to have a beautifully blurred background, so you focus only on your subject. In that case you would use f2.8 or below.

Please remember that aperture is only one of the three parameters that determine the EXPOSURE.

1.- Aperture - Controls how much light enters your lens.
2.- Shutter speed - Controls how long the shutter stays open.
3.- ISO - Controls the camera sensor’s sensitivity to light.

But other factors affect your choices.

- Aperture also controls the depth of field (focus)
- Shutter speed affects whether the motion is frozen or blurred
- High ISOs introduce grain into the image

Each scene needs an optimal combination of settings.

Each parameter can be changed independently in manual mode, but they are not really independent, because changing one setting can alter all of the others.

It is the combination of all these settings and how they interact within each other that makes the perfect exposure!

Please download this FREE graphic that will help you visualise these concepts and understand Aperture, Shutter Speed and ISO better.

If you want to deepen your passion for photography and find the confidence to use all the buttons on your camera, please check out my course ‘Beginner’s Photography: Basic Camera Use and Theory’.