What is Aperture? Photography Tutorial #BACKTOBASICS

what is aperture

I love getting emails from readers with photography related questions and today I want to start my #backtobasics series of tutorials. 

It's easy to buy a camera and dive straight in. Leave the manual neatly in the box un-thumbed and start snapping. I know, I've done it!

But understanding the principles and basics of photography will help you master your camera, whether it be a phone camera, compact, DSLR or anything in between.

I will be posting a series of easy to follow photo tutorials which will take us on a journey from the fundamental principles right through to editing processes and tips to ways to use your beautiful photos.

Everything is easier to understand in bite size pieces. Then when you piece them all together you will feel a light go off in your mind and bingo, you will start taking better pictures!

Today is about Aperture

Light passes through your camera lens through a hole. This hole decides how much light to let onto your camera sensor. Aperture is the size of that hole inside the lens. Just like how your pupils react to light. If you shine a light in your eyes your pupils will get smaller, but in a darker room they will dilate to try and let as much light in as possible.

Put your hands together in front of you. 

what is aperture

The smaller the hole the less light that can pass through.

Aperture is measured in F-numbers. This is the measurement of the diameter of the hole. 

Aperture is referred to as full stop F-number or F-stops. If you look at a lens you will see it has an F-stop range or number.

There are a number of different sets of F-numbers but the most commonly used are:

ƒ/1.4 2 2.8 4 5.6 8 11 16 22 32

It might sound confusing but the lower the F-number, like ƒ/1.4, the bigger the hole and therefore the more light that is allowed to the sensor.

The higher the F-number, like ƒ/22, the smaller the hole and the less light that is allowed through to the sensor. 

The amount of light that reaches the sensor affects the depth of field and the amount of your image that is in focus.

So... the lower the aperture, like ƒ/1.4, the bigger the hole and the more light, but this will give you a very shallow depth of field. You know the lovely blurry background shots with a very crisp focus in the foreground.

Take a look at this set of photos.

what is aperture

As the aperture number increases, the hole gets smaller, the less light reaches the sensor, and the more in focus the background becomes.

Look at the holes on the peg board (Which I was kindly given by Red Candy, I'll be sharing a post on that soon) higher the F-number the more in focus they become.

I love shooting on Aperture Priority and my signature style is to use a low F-number, typically ƒ/4, to get a shallow depth of field and a very blurry background.

Compare these 2 photos. The one on the left is a low aperture, ƒ/4, the one on the right, ƒ/22.

what does aperture mean

You can see how the leaves become more crisp on the right, but my familiar style would be the photo on the left.

Phone apps like Big Lens (iPhone) or Shot Control (Android) will allow you to play with aperture. I use an iPhone and tap the focus square until I am happy with the focal point and depth of field.

Have a play with your camera on Aperture Priority (Look for the AV or AP setting) and compare how changing the aperture alters your photo. If you are taking a picture of a landscape you may want to try a higher F-number, to get the whole view in focus, but if you are taking a picture of your child, a lower F-number might help keep the focus of the photo on their face.

Don't forget to leave me any questions on the blog post and if you take any photos on Aperture Priority tag me or tweet me so I can see! I love shooting on Aperture Priority because I have control over the atmosphere I create in a photo, by altering the depth of field.

what is aperture

Next up is shutter speed...