Bookmark and Share
All images and content are property of Alexis Miller Photography. Please do not download, reproduce, or redistribute images or content in any way.

You may contact Alexis at:

Let's Talk About Aperture

The word aperture refers to how large the opening of your lens is. It can be a tricky concept to understand. Aperture is defined by f/stops. The smaller the f/stop number, the larger the opening. The larger the opening, the more light can get in, and the more blurry the background.

Try setting your camera to Aperture priority mode (it's usually indicated by a capital "A" or an "Av." Now, set the f/stop to the lowest number that your lens can go. (Some lenses can go all the way to f/1.2, but most kit lenses only go to about f/3.5.)

You'll want to avoid using your flash for this, so unless you have fantastic window light, try this experiment outside. Once you have your aperture set to the lowest number, try moving in fairly close to a subject, and take the picture. The background should be very blurry. Now, change your aperture to the highest number that your lens will go (most often f/22.) From the same position and angle, take the picture. Notice how much more of the background is in focus - it should be virtually everything.

One more thing to remember about Aperture: If your aperture is set at f/22, the opening is very small, and very little light can get in to hit the image sensor (or film). To allow for a properly exposed photo, the shutter has to stay open for a much longer period. Likewise, if your aperture is set to f/1.8, the opening is very large, and the shutter has to stay open for a much shorter period of time to get a proper exposure.

This photo was taken at f/1.8 at 1/80th of a second. (The shutter was open for 1/80th of a second.) I generally don't like to have my shutter speed at less than 1/60th of a second without a tripod - the photos turn out blurry.

This photo was taken at f/22 at 1.5 seconds. (The shutter was open for 1.5 seconds.) I used a tripod and the camera's self timer (a remote works great too, but I don't have one) to avoid touching and moving the camera at all while I was taking the picture.


Mini said...

Excellent tutorial!

BeeBopp23 said...

Hi! I found your blog thru Clickin' Mom's. Somebody suggested it for tips and such! Just wanted to take the time and tell you that its very helpful! Thank you! I'll be adding you to my favorites!

Sarah McVey said...

WOW! I'm new to your blog, and I'm loving all the goodies and info! TFS!