what is aperture - aperture and fstop explained for beginners

What Is Aperture? Aperture & f-stop explained!

What Is Aperture?

A simple explanation of Aperture & F stop!

When it comes to learning photography basics, the terms can be a little daunting! Nowhere is this more the case than with aperture. The problem is there aren’t a lot of good tutorials explaining what aperture is and how aperture works – So we decided to sit down and tackle aperture in depth. Not just the technical definition for aperture and how aperture is calculated, but how using aperture affects your photography. Aperture is one of the most important components to photography, so its essential to have an understanding of how aperture works and how to know what to set your aperture to! Ready? Lets dive in.

Common questions people ask about aperture:

Why does aperture affect depth of field?

Simply put, the aperture of a lens is the size of the hole allowing light to pass through to the camera. The larger the hole, the greater the angle of light entering the camera, which results in a shallower depth of field. For an in depth explanation, watch our video explanation of aperture and depth of field!

Is aperture the same as f-stop?

No. Aperture is technically the diameter of your lens opening that allows light into the camera. But aperture is commonly incorrectly referred to when talking about a lenses f-stop, which is a measurement of how much light a lens funnels into the camera. F stops are calculated by dividing a lenses focal length by its aperture. To make this less confusing, check out our video which explains the differences between aperture and fstops.

Why are lenses called “fast”?

A lens with a larger aperture lets more light into the camera. Lenses with larger apertures are called fast because this allows the photographer to use a higher (faster) shutter speed!

What is the theoretical fastest lens possible?

There is no theoretical limit to the aperture of a lens or the fastest possible lens stop. It is only limited by the practicalities of size, weight and cost to produce such large, heavy and impractical lenses! The fastest lens ever made was f0.33, and was made for show purposes only as it was ridiculously heavy and impractical.

Why is a lower f-stop better?

A lower f-stop means more light enters the camera, which makes it easier to expose your image without having to compensate with higher iso or a slower shutter speed which risks motion blur.

What is an iris?

On a camera, the iris is the mechanical device inside the lens that expands and contracts to enlarge and shrink the size of the lens opening. This determines the aperture of the lens and the amount of light that reaches the camera.

What does the f in f-stop stand for?

The f in f-stop stands for focal length – Which is the length of the lens barrel, measured in millimetres.

How is aperture calculated?

Aperture is calculated by measuring the diameter of the lens opening. The fstop of that lens is then calculated by dividing the focal length by the length of the aperture.