Aperture and other photo basics can induce yawns in the most eager of new shutterbugs, but once these basics are understood, the rest of photography comes easily into focus. Aperture, shutter speed and ISO are all terms good to know, whether you have a point-and-shoot or professional camera. This article explains aperture and provides tips for using it to create better photographs to frame on your wall.
To best understand aperture, consider how the irises of your eyes widen and narrow to allow more or less light into the pupil. Like your irises, the camera's lens diaphragm narrows and widens to let in less or more light. Thus, the aperture dictates the exposure (the darkness or brightness) of the photo. The aperture also has another important function which we'll look at shortly.
"Aperture" refers to the size of the camera's lens diaphragm and is measured in F stops. The smaller the F Stop number, the wider the aperture. This is where it's easy to get confused. Actually the F stop numbers are ratios, which is why the bigger the F Stop number, the smaller the size of the aperture.
In addition to controlling light, aperture also controls depth of field. To better understand this, make a fist and hold it in front of your eye. Now slowly open your hand. See how the focus changes? Sure you can see more through the bigger opening, but when the opening in your fist is small everything is in focus? Try it again and see how when you open your fist, the object closest to you will come into focus while objects further away will be fuzzy. This is how aperture determines depth of field, that is how much of a photograph is focused.
If you are taking pictures in Auto Focus (AF), the camera will attempt to focus on what it sees as the main subject, but often it may not be what you want.
For this reason, many cameras have an Aperture Priority setting to help eliminate this problem. This allows you to set the aperture and then it automatically adjusts the shutter speed to compensate for the larger or smaller aperture. For example, if you set the aperture for a landscape, it narrows it and therefore lets in less light. The camera would automatically lengthen the time the shutter stays open so that your photo isn't underexposed (too dark). Aperture Priority isn't exact, but this is how it usually works.
Now if you have an SLR and are taking pictures in manual mode, you can adjust the shutter speeds and aperture separately.
Most will have a camera with preset modes, such as portrait, landscape, sports, etc.
When the mode is set for landscape, the aperture automatically narrows so everything will be brought into focus. At the same time, the shutter speed automatically slows, thus leaving the shutter open longer to compensate for the lessened amount of light streaming through the diaphragm.
When you switch to portrait mode and focus on a person in front of you with the landscape in the background, the camera will bring your subject into focus, making the person stand out more than the landscape. And it will speed up the shutter speed so the picture isn't overexposed by the additional light allowed in with the larger aperture.
Remember that the smaller the aperture, the greater the F Stop number and the greater the depth of field.
Understanding photography basics like aperture is not only important for those using manual settings or Aperture Priority, it also helps those using preset modes. Here are three preset modes you should better understand:
- Portrait: How much the background blurs when using this mode depends on your camera and the distance between your subject and background – a minimum of 10 feet works best. This mode can be used for any subject you want to bring into focus while taking the background out of focus.
- Landscape:(called "Infinity" on some cameras): This is the mode depicted by the mountain peak or figure 8. You can use this for anything where you want everything in the picture to be in focus, such as seascapes, cityscapes or your garden.
- Macro: This mode, depicted by the tulip, opens the camera's aperture extra wide so that you can take extreme closeups without the blur caused by not enough focus. Depending upon your camera, you should be able to get anywhere between an inch to a foot of your subject. When preparing to take pictures outdoors of things like flowers, keep in mind that due to the slower shutter speed, even the tiniest movement of a petal can cause blur. Also remember to focus on the subject that you want in focus, whether it be a caterpillar's eyes or a butterfly's wings.
Just applying this knowledge can help you take some beautiful photos that you'll be proud to display in your home.
