Photography is both art and science. As a beginner photographer, you must have been told a dozen times that taking the perfect picture requires talent to know what needs to be in and out of the frame, what time of the day reflects the perfect light on your subject and which angle will give you the most stunning shot. This is all true; however, this is not all. In addition to all these aesthetical elements, there is the technical aspect you need to understand as well.
One of the biggest challenges for a new photographer is to master the art (and science) of setting the perfect aperture, which is one of the most important features of the all-important “exposure triangle”. Setting an aperture may sound too technical, but at the end of the day, it’s your talent and eye for detail that determines the value at which it would give you the perfect light and sharpness.
What is an Aperture?
Before you get into the science of it, you need to understand what an aperture is, and what it does. How many times have you heard photographers say “the exposure isn’t right”? Well, that is what your aperture controls. Let’s define it in the simplest of terms; the aperture is a small hole within your camera’s lens. This hole controls the amount of light that passes through the lens. It also controls one more major aspect: the depth of field. Now it gets a little technical – the size of the hole is directly proportional to the amount of light that enters the lens and inversely proportional to the depth of field.
What is Depth of Field?
You must be getting ready to Google the term “depth of field” but I can quickly explain it without boggling your mind by writing down complex definitions. Simply put, it is the part of your photograph that will appear sharper than the rest. In order to understand how the light and depth of field are managed through the aperture you need to carefully read this: To get more light and a shallow depth of field, you need a large aperture; for less light and a large depth of field, you need a smaller aperture. Now let’s break these two lines into simpler words.
Light and Aperture
When you open a large aperture, it allows more light to enter your lens, giving your photograph more exposure. This setting is ideal when you need your photograph to be brighter; it helps in settings where natural light is not enough. Similarly, when there is too much light and you fear over-exposure, or if you want your photograph to appear darker, you need to have a smaller aperture so you can minimise the amount of light that enters your camera lens. In a nutshell: for bright photos, set your aperture at a lower setting and for darker photos, the setting needs to be higher.
The Depth of Field and Aperture
You have a foreground and a background in your photograph. Your subject can be placed both in the foreground and the background. If your subject is placed in the foreground and you want the focus to be on that subject, you can make the foreground sharp and blur the background out. For this, you need a shallow depth of field or focus, which means your aperture will be large. When you want both your foreground and background to appear sharp, you will need a larger depth of field, which means your aperture will be small. Speaking in terms of aperture settings, for a larger depth of field, you need to set your aperture lower, and for a shallow depth of field, the aperture will be set at a higher value. Let’s make the whole concept even simpler, you can adjust the blurriness of your background with the settings of your aperture.
Now let’s study the aperture setting.
Aperture is measured in f-numbers, which is the ratio of the lens’ aperture diameter to the lens’ length. The numbers f/2, f/4.0, f/6.0 and so forth on your camera are your aperture settings. Now comes the part that confuses all the beginners, the higher the number, the lower the (aperture) setting; f/2 is not bigger than f/4. I will try to explain this as clearly as possible: if you want a bigger aperture, then you need to set it at a lower number, and vice versa. Aperture set at f/2.8 is bigger than the one set at f/16. Remember, these are just the basic rules. You can use them to create aesthetically pleasing photographs or photographs that make us see new and unique ways to manipulate light. It boils down to your creativity and imagination!