Aperture and other technical photography basics can induce yawns in the most eager of budding shutterbugs, but once these basics are understood, the rest of photography easily comes into focus. Aperture, ISO and shutter speed are all important terms to know, whether you have a point-and-shoot or a professional camera. This article explains aperture and provides tips for using it to create better photographs so you’ll be proud to display them in a wall picture frame.
To better understand aperture, think about how the irises of your eyes get bigger and smaller to allow more or less light into the pupil. Like your irises, the camera’s lens diaphragm widens and narrows to let in more or less 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 this opening and is measured in F stops. The smaller the F stop, the wider the aperture. This is why it can be confusing. Actually the F stop numbers are ratios, which is why the bigger the F Stop number, the smaller the size of the aperture.
Besides controlling light, aperture 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 larger opening, but notice how when the opening in your fist was small, everything that you could see was equally 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 shooting in Auto Focus (AF), the camera will attempt to focus on what it perceives to be the main subject of the photograph, but the results 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 aperture. For example, if you set the aperture for a landscape, this narrows it, thus letting in less light. The camera would then automatically increase the amount of time the shutter stays open so that your photo isn’t underexposed or too dark. Aperture Priority isn’t exact, but this is how it usually works.
Now if you have an SLR and are shooting in manual mode, you can adjust the aperture and shutter speeds separately.
Most will have a camera with preset modes such as landscape, sports or portrait. When the mode is set to landscape, the aperture automatically narrows to bring everything into focus. At the same time, the shutter speed automatically slows down, leaving the shutter open longer to offset the smaller amount of light coming through the lens diaphragm.
When you switch to portrait mode and focus on someone in front of you with the landscape in the background, the camera will make your subject in focus and make them stand out from the background. And it will speed up the shutter speed so the photo isn’t overexposed by the extra light allowed in with the larger aperture.
Remember: the smaller the aperture, the greater the F stop number (because it represents a ratio not a whole number) and the greater the depth of field.
Understanding photo basics like aperture is super important for using manual settings or aperture priority but also helps those using preset modes as well. 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 any picture where you want everything in focus like landscapes, cityscapes or a picture of your garden. And for shots of breathtaking vistas, try framing them in a panoramic picture frame to make your images really stand out.
- 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 on your camera, you’ll be able to get anywhere within 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 part of the subject that you want most in focus, whether it be a butterfly’s wing or a caterpillar’s eyes.
Just applying this knowledge can help you produce some beautiful photographs that you’ll be proud to display in a gallery picture frame on the wall.