Photography 101: Mastering Your Aperture
Aperture is one of the three key factors to control your exposure. It’s the mechanical iris inside your camera lens that regulates how much light reaches your sensor. Just like how your eyes adjust to light, the aperture helps your camera see in varying lighting conditions. You can adjust the aperture electronically in your camera, or physically by rotating a ring on your lens.
Reading aperture
Aperture is indicated by the character ‘f’, followed by a number, like f/2.8. In photography jargon, it is commonly referred to as f-number or f-stop. Something you may need to get used to is that a lower number means more light, while a higher number means less light. So, an aperture of f/2.8 lets in more light than f/11.
As you grow more accustomed to aperture and its values, you will notice that your camera will allow you to fine-tune your setting by 1/2 or 1/3 stop increments.
To give you a better overview, below you will find a list with the most common full-stop apertures in photography. Though the number difference between each stop isn’t linear, the amount of light between each stop is either doubled or halved, assuming that your shutter speed and ISO settings remain unchanged.
Common f-numbers
f/1
f/1.4
f/2
f/2.8
f/4
f/5.6
f/8
f/11
f/16
f/22
f/36
Aperture and depth of field
An important concept related to aperture, is ‘depth of field’. In a nutshell, depth of field is the area of your photo that is in focus. This is a concept that deserves its own article, but I want to give you enough information to help you understand how it all relates.
In general, a larger aperture (lower f-number) allows for a shallower depth of field. This technique helps you isolate and emphasize the subject in your photo. On the other hand, a smaller aperture (higher f-number) will have more of the photo in focus. This is common in landscape photography where you want to show more of the scenery front to back.
Please keep in mind that depth of field is not solely dependent by aperture. There are other factors that affect it. But, as mentioned earlier, this will be covered in a separate article.
Limitations and considerations
Something you should know is that the maximum aperture, or the f-number that lets in the most amount light, is limited by the lens. Now, you may be thinking: “Then why are companies still making lenses with smaller maximum apertures?” or “Then I might as well just go for the lens with the largest maximum aperture.” I can understand your way of thinking. However, reality isn’t this simple.
See, larger apertures generally require more complex and expensive constructions, making them heavier and costlier. You will have to think carefully about your aperture needs when you are in the market to purchase your next lens.
Now that you have a better understanding on how to control aperture, you can explore further to master the concepts of shutter speed and ISO.