The depth of field is how much of a photo is in focus or how much of a photo is sharp. A photographer can use depth of field to create depth and different perspective in a photo. It can help center the attention on just the subject, or it can expand the focus to other elements in the photo. A small depth of field is used when you want all the attention to be on the subject. This creates a blurred background without focus. A long depth of field is used when a photographer wants every part of the photo to be sharp and in focus. This can be helpful you think the background of a photo adds to the power of the picture.
The photo above is a great diagram which helps show how a small and long depth of field work.
In this post I am going to be showing you how aperture numbers can affect the depth of field in your photos by using different aperture numbers to create larger and smaller depth of fields.
In these photos, I took the same photo from the same distance, but I changed one thing in each photo. The one component I changed was the aperture number. The aperture number is directly related to the size of the opening on a camera lens. Higher numbers indicate smaller openings and lower numbers indicate bigger openings. You can see the affects of the aperture number in these photos because of the depth of field. The photos with a lower aperture have a very blurred background while the photos with higher aperture numbers have a more focussed background. This happens because the light that goes into the camera lens is perceived as blur. Therefore if there is more room for light to enter, then the background will blur more. This creates a more shallow depth of field. A larger depth of field is created with smaller numbered apertures, because there is not enough of time for the light to create blur in the background.
In these photos the depth of field is affected, because I moved back after taking the same photo with three different aperture numbers. The farther back I stood, the more in-focus objects become in the photo. As you can see from the photos above, the farther away from the flowers I am, the more in-focus the things surrounding the flowers become. In addition to the background blur chaning, the amount of flowers and objects in focus is changing as well.
In all five of these pictures, I used a small depth of field to help the subject of each photo really stand out. I did this by using a small aperture number which created a larger opening in the lens.
I chose this photo as my featured image for a number of reasons. First of all I love how the photo shows the goofy, free, young spirit of a young student. The second reason I love this picture is because he was so excited to get his picture taken. The last reason I like this picture is because I love how the boy is the main focus of the picture. This was achieved because the background is blurred in the photo.
