I know how it goes. You saw that fat, balding guy on vacation with the huge black camera hanging from his neck, and you just knew if you had one that big, too (I’m talking about the camera people. Focus.), you’re photos would be amazing. You’re totally better than that point and shoot your mother gave you for your birthday, right?!?! So you bought this ginormous camera. And, now, you have no idea what to do with it. Reading the instruction manual is out of the question because it’s written in Russian . . . or might as well be. I know.
To help you tame this beast you went out and spent a small fortune on, I’m starting a little photography 101 series. Nothing earth-shattering or mind-blowing . . . just the basics. So you can actually turn your camera on and use it. This first lesson deals with the basic premise of photography . . . exposure. What is it? What affects it? I’ve got several more topics already planned, but if there’s something in particular that you’d like to know about, I’m taking requests, so leave a comment, and I’ll do my best to cover it.
Are you ready?? Here it goes.
LESSON 1
How many of you newly christened DSLR owners know that you can tell your camera what to do? Your camera has several shooting modes (other than automatic), which allow you to choose what an image will look like as opposed to your camera doing it all for you. How do some photographers get those awesome silhouettes against a beautiful sunset or stop a speeding car? By manually controlling the exposure of the image. Are you ready to do more than point and shoot? If so, read on, my friend.
Do you see the M, A, S, and P up there? Those letters designate the various shooting modes in addition to auto (point-and-shoot mode). M stands for manual, in which the photographer manually sets both the camera’s aperture and shutter speed. A stands for aperture priority, in which the photographer sets the aperture and the camera sets the appropriate shutter speed. S stands for shutter priority, in which the photographer sets the shutter speed and the camera sets the appropriate aperture. P stands for program, in which the photographer can program the camera to certain settings for certain situations. The letters are not always the same depending on which kind of camera you shoot, but the modes are.
To stop pointing and shooting, you must switch your camera off of the little green camera icon. Which setting you choose is up to you. For beginners, it’s easier to start with one variable (such as aperture priority or shutter priority) until you get the hang of it. So go on. Change the mode. I promise the camera won’t blow up in your hands.
The basic principle to taking good photos in a mode other than auto is exposure. In photography, the term “exposure” refers to the total amount of light allowed to fall on the photographic medium—the image sensor in your fancy new DSLR (or the film in your antique film camera). There are 3 components to exposure: ISO, aperture, and shutter speed. You can manually manipulate all of these on your camera. I will discuss them in turn. And, don’t worry, I’ll go slow.
ISO refers to the camera’s sensitivity to light. It correlates to film speed. Some of you actually remember film, right? Well, if your DSLR is set to an ISO of 400, that’s pretty much the same as when you put 400 speed film in your film camera. Why does ISO matter? It affects the amount of light you need to properly expose your image. The higher the ISO, the less light that is needed to achieve correct exposure. 100, 200, 400, 800, and 1600 are a typical range of ISO settings for most cameras. 200 or 400 is a pretty standard and versatile setting for most lighting situations. But, beware, as you increase your ISO (which may be necessary in low-light), you introduce “noise” (what we called film grain in the old days) to your images, especially in the darker areas.
Aperture (also known as an f-stop) refers to the diameter of the hole or opening in your lens (see the hole!) through which light travels into your camera.
Aperture in your camera works just like the iris in your eye. The bigger that hole is, the more light that comes through. As you can probably figure out, more light = brighter exposure, while less light = darker exposure. Easy enough, right?!? Well, hold on to your hat because this is where it gets a little tricky.
F-stops are valued like this: f 1, 1.4, 2.8, 4, 5.6, 8, 11, 16, 22, 36. For some moronic reason, the numbers and the amount of light let in are INVERSELY related. (Don’t ask me why . . . I might have a stroke.) The smaller the number, the more light that will travel through the opening (f 1 lets in the most light; f 36 lets in the least light). Each “stop up” (or the next highest number) lets in half as much light as the previous stop. So, f 4 lets in half as much light as f 2.8.
In addition to controlling how much light enters your camera, aperture also affects thinks like depth of field—how much of your image is in focus. Depth of field is one of my favorite things to play with, but it’s a little deep for the first lesson. If you want to learn about depth of field, you’ll have to stay tuned (hey—subscribe to the blog!) because I will cover it in another post.
Shutter speed controls how long the shutter in your camera is open. When you press the button to take a picture, that action opens the shutter. The shutter allows light to flow into your camera, through the aperture opening, and onto the image sensor.
Shutter speeds are calculated in seconds . . . or, more accurately, fractions of seconds. Your camera will show you numbers like 4, 8, 15, 60, 125, 250, 500, 1000. What these numbers really mean is 1/4 of a second, 1/8 of a second, 1/15 of a second, and so on.
Unlike aperture, shutter speed values are logical—the higher the number, the faster the shutter will open and close. This means that a shutter speed of 1000 will only allow the shutter to stay open for 1/1000th of a second, which in turn, will not allow much light into your camera. Slower shutter speeds (smaller numbers) are needed for lower light situations, while faster shutter speeds (bigger numbers) are needed in brighter situations.
Shutter speeds also control things like motion in your image. But—you guessed it—I’m not getting into motion today.
As I told you at the beginning, all three of these things (ISO, aperture, and shutter speed) work together to control exposure. If you adjust one, you will have to adjust the other two to compensate and achieve proper exposure.
The least of your worries is ISO. Most of you can set it and forget it. I recommend an ISO of 200 or 400. If you need to shoot in a low light situation, you will need to increase it.
The main players in exposure are aperture and shutter speed. And, the pioneer photographers throw us another curve ball here because THEY ARE INVERSELY RELATED, TOO! As a general rule, the lower the number of your f-stop (f 1.8), the higher the number of your shutter speed will be (1000, 1600), and vice versa.
Confused yet?
Now that you know what ISO, aperture, and shutter speed are and how they work, next time I will tell you how to tell if your image is properly exposed. We’ll delve into intriguing topics like reading light meters. I know it’s exciting, but keep your pants on. The next lesson will be here soon enough.
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by Heather
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