Camera Aperture Settings

By beginnerphotography | Uncategorized

Apr 06

Are you confused about camera aperture settings?

Let’s walk through what aperture is, what it can do for you, and how it works.

First, a question I am often asked by aspiring photographers is, “how do I blur the background?”

Well, aperture happens to be one of the main photography tools to accomplish this.

Let’s make our way through this as easily as possible!If you find it confusing just be patient – you may have your “now I get it!” when you least expect it, just like I did!

First of all, very simply, your camera operates with aperture settings because it’s part of the complete process of taking photos.

Aperture is:

  • the amount of light being admitted through the lens.
  • how much light depends upon the aperture setting.
  • aperture is often referred to as the f-stop.
  • aperture can affect the depth-of-field.
  • depth-of-field relates to how much of your photo is in focus.
  • a background intentionally blurred has a shallow-depth-of-field.
  • more in focus has varying amounts of a greater-depth-of-field.


Is your camera always “doing something” with the aperture, in other words, adjusting the amount of light “coming in?”


The aperture will be “chosen” by the camera when you shoot in the Auto Mode.

The aperture will be determined by you in the Aperture Priority Mode.

In this diagram, above, the green symbol indicates Auto Mode, the Av indicates Aperture (Value) Priority Mode. A single letter A is used, too.

When you’re taking photos using the automatic setting the camera is determining a number of factors.

One factor is – how much light is being “allowed in?”

In other words what is the f-stop, or aperture, being used?

Are you thinking – beats me and why do I care?

Well, aperture will help you:

  • unleash your creativity and do fun things like blur the background.
  • it’s helpful in lower light situations when you can open up the lens diaphragm to let in more
  • light, to help with a faster shutter speed.
  • shoot in a “semi-automatic” mode as you begin to figure things out.


Let’s take a look at the diagram, below, showing examples of the lens diaphragm opening at different apertures.

As you can see, there is an f-stop, or aperture number, relative to the size of the opening and how much light is being admitted.

The smaller the number = the larger the opening = the ability to create intentional background blur.

t took me a long time to have this make sense as I attempted to relate smaller number, larger opening, less in focus, until it was explained as:

the smaller the number the less the amount of the subject in focus.
the larger the number the greater amount of the subject in focus.

Put another way…

smaller number, less in focus = shallow-depth-of-field.
larger number,  more in focus = greater-depth-of-field.

When you’re shooting in the automatic mode the aperture “size” being used depends on the “instructions” from within the camera.

In other words, it’s doing all the figuring out for you.
If YOU wish to control the amount of light being admitted you will need to change from Auto Mode to Aperture Priority Mode.

When you shoot in Auto Mode the camera figures out both aperture and shutter speed.

When you are using the Aperture Priority setting the camera is still figuring out the shutter speed for you.

Your camera will reveal the aperture to you…

F4.5 is the aperture value.

Can you determine how much light is being admitted, based on the aperture data?

A lot or a little?

Take another look at the chart above if you’re not sure.

(The 90 indicates 1/90 second, which is the shutter speed).

If you figured out F4.5 is more light and this will help blur a background, which is shallow depth-of-field, you are absolutely right!

Great going!

Recognizing the numbers relating to aperture is a great place to begin as you familiarize yourself with aperture settings.

You can do this even with the camera in the Auto Mode as you become familiar with the numbers.

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