APERTURE : Understanding Exposure in Digital Photography

Aperture in Digital Photography

On our series of demystifying photography, we’ll be looking at one of the three cardinal factors that determine exposure in photography; which is Aperture. The other two are ISO and Shutter speed. Before we go ahead, it’s advisable¬†we have a good knowledge of the structure of a DSLR camera

What Is Aperture

Aperture can be defined as an opening in a lens through which information in form of light travels into the camera body/structure. This could vary in size. The larger it is, the more light that gets into the camera.

Aperture Size

The size of the aperture can be controlled by the Iris. In Digital Photography, the aperture is measured in f-numbers (for example f/8). The f-numbers or f-stops can be used to describe how wide or narrow the aperture is. A smaller f-stop means a larger aperture while a larger f-stop translates to a smaller aperture. This is another area photographers find confusing but once you understand the ideology, it sticks.

Below a graphic representation of Aperture.

Aperture Explained
Aperture Explained

Depth Of Field.

We can hardly discuss Aperture without making reference to Depth of Field. Depth of Field can be defined as the amount of your shot that is in focus. A large Depth of Field means that most of your image would be in focus. This can be produced using a small aperture (large f-number/f-stop) such as f/16.

Large Depth of Field
Large Depth of Field (Large F-number/Small Aperture) F-stop f/13 Exposure time 1/160secs ISO 160

A small or shallow Depth of Field can be seen as an image with only a portion of it in focus while the rest of it remains blurry or fuzzy.

Shallow Depth Of Field
Shallow Depth of Field (Small F-number/Large Aperture) The image was taken at the LetstalkphotographyPH meeting f-stop f/1.8 Exposure Time 1/200 secs, ISO 1600 Focal Length 50mm Subject Distance 2.5m Metering Mode Centre Weighted Average No Flash

DSLR Lenses are manufactured to have specific values on how wide or narrow the aperture can get. The lens specifications usually state the largest f-stop and the smallest f-stop. A lens with a maximum f-stop of f/1.2 is considered to be a fast lens because it allows more light to pass through compared to a lens with a maximum aperture of f/4.0

Here's a brief video produced by Olufemii Tutorials that also explains Aperture

We tried to keep things as simple as possible while explaining Aperture as it relates to Exposure in Digital Photography. Feel free to share your thoughts in the comments section below.



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Author: Forte

Nigerian Wedding, Beauty, Portraits And Fashion Photographer | Cinematographer | 3D Animator | Motion Graphic Artist | Graphic And Web Designer

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