Aperture is simply an opening within the camera's lens that allows varied amounts of light to reach the sensor.
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Aperture of f/22
Photo courtesy of Wikipedia
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Aperture has been compared to the iris of the eye. The iris's main function is to control light levels within the eye. The pupil (round opening at the center of the iris) widens in low light to allow more light into the eye and becomes narrow in bright light to restrict the amount of light that gets into the eye.
The camera's aperture works in the same manner as the pupil. A wide aperture allows more light to pass into the camera and a narrow aperture allows less light to enter.
Something you'll need to know is that aperture is expressed in f-numbers called f-stops. The larger the f'stop ex. f/1.4, the smaller the opening. The smaller the f-stop ex. f/8, the larger the aperture. This is where it gets a bit confusing. It seems as though this should be the other way around right? I know how you feel! This was a little puzzling for me at first, but the more I used this feature, the less difficult it was to remember. Don't worry, you'll get it! Another great feature of the Nikon D40x that you will find helpful is the visual representation of the aperture found on the monitor in all shooting modes. It's features like these that make this camera a great DSLR for amateur photographers.
The main job of aperture other than controlling light is to determine the amount of focus your photo has, also known as depth of field (DOF). Here's where the creativity comes in. If you select an aperture of f/22 for example (large depth of field), a majority of your subject and background will be in focus. An aperture of f/3.5 (shallow depth of field), will sharpen your subject and make your background appear softer and blurred.
The photos below show a sampling of the depth of field difference between f/4.5 - f/22. Notice how much of the photo is in focus at each stop.
Congratulations! You are about to embark on a journey that will change your life forever as an amateur photographer...taking your camera off automatic mode! This was an exhilarating step for me. Practicing with your camera is the best way to make sense of what you are reading. I guarantee it! Here's how to get started with the Nikon D40x.
Step 1. Rotate the mode dial to A.
Step 2. Rotate the command dial until you arrive at the desired f-stop.
Step 3. Focus on your subject and press the shutter release button.
In this mode, the camera will select the shutter speed that will result in the best exposure for the shot.
Practice shooting pictures with the different f-stops and observe the difference of each shot. You will love the effect and aperture will become your new best friend.
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Aperture measured in f-stops
Photo courtesy of Wikipedia
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| f/5- subject is sharpened and the background is blurred |
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| f/22-both subject and background are in focus
When photographing landscapes you may want to use a large depth of field (large number) where everything will be in focus. For portrait photography, using a shallow depth of field (small number) is effective because it draws attention to your subject making it the focus of the picture while blurring out distracting elements in the background.
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The photos below show a sampling of the depth of field difference between f/4.5 - f/22. Notice how much of the photo is in focus at each stop.
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| f/22 - everything is in focus |
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| f/16 - background of the image is slightly blurred (purple) |
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| f/10 - more of the background is blurred (purple & blue) |
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| f/ 6.3 - about half of the image is blurred (purple to green) |
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| f/ 5 - most of the image is blurred here (purple to yellow) |
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| f/4.5 - very small area of focus on the red paint, the other colors are blurred. |
Congratulations! You are about to embark on a journey that will change your life forever as an amateur photographer...taking your camera off automatic mode! This was an exhilarating step for me. Practicing with your camera is the best way to make sense of what you are reading. I guarantee it! Here's how to get started with the Nikon D40x.
Step 1. Rotate the mode dial to A.
Step 2. Rotate the command dial until you arrive at the desired f-stop.
Step 3. Focus on your subject and press the shutter release button.
In this mode, the camera will select the shutter speed that will result in the best exposure for the shot.
Practice shooting pictures with the different f-stops and observe the difference of each shot. You will love the effect and aperture will become your new best friend.
