Of all the things “essential” to good photography, light is paramount. In fact, “photos” is Greek for “light.” That being said, the key to understanding photography and how to take great photos is understanding how to manipulate the available light.
Your camera is equipped with two (really three– more about that later!) mechanisms that help you manipulate light. In fact, if you have a basic point-and-shoot camera, it probably does it all on its own! These two things are the camera’s aperture and shutter speed. Let’s tackle aperture first!
The aperture is a circular mechanism inside your camera that opens and closes when you take a picture. Basically, the more open the aperture, the more light will be let in when you take a picture. The more closed the aperture, the less light will be let in for your picture.
You’ll need to dig out the manual for your camera to find out how to adjust the aperture on your individual camera. Whether you use a point-and-shoot or a SLR (single-lens reflex) camera, more than likely, you should be able to adjust your aperture.
Aperture is “measured” in f-stops. It may seem backwards, but the larger the number, the smaller the opening. For example, f/32 would be a very small opening, whereas f/1.4 would be a very large opening. Too much light will result in an OVERexposed photo, washing out your image, whereas too little light will result in an UNDERexposed photo, making your picture too dark.
You can also use your aperture settings to adjust your depth-of-field. Depth-of-field refers to how much of your picture is in focus. Sometimes you want everything to be in focus for your photo, sometimes a blurred background is more desirable. The smaller your f-stop number, the smaller your depth of field will be, making your background blurry. Likewise, the larger your f-stop, the larger your depth of field, creating a crisper photo with all of your background in focus.
On a sunny day, I took these four photos of the same flower in the same lighting conditions.
This one was shot with an aperture setting of f/5. This let in way too much light for a sunny day.
This one was shot with an aperture setting of f/16. It’s still a little bright, but as you can see, the depth of field is smaller (only the flower is really in focus), which can be very desirable for portraits or close-ups. In this case, you would adjust your shutter speed to get just the right exposure. More on that next time!
This one was shot with an aperture setting of f/22. The color detail is much better on the flower and some of my background is still blurred.
This last one was shot with an aperture setting of f/32– a VERY small aperture setting. This was a very sunny day so I didn’t need to let in much light at all. As you can see, I still have great color detail and the depth-of-field is much larger. My whole background (pretty much) is in focus. (You might have to click on the photos to see them full-size to really be able to tell!)
Alright– now go experiment with your aperture settings and we’ll discuss shutter speed next time!