I’ll be honest and say that it took me a while to really understand the triangular relationship between aperture, shutter speed, and ISO. I took an entire semester of two beginner photography classes, and though I passed them both with straight A’s, neither instructor got across to some of us students exactly how the elements of exposure really work.
The biggest and what should have been the most obvious reason why this happened is because neither instructor actually had us take out cameras, plop a fast lens on and learn how different camera exposure settings have a reciprocal effect one another. They lectured about exposure settings but never thought we needed to learn hands on. I kid you not about this.
There are entire books written about understanding exposure, and the best I recommend is Bryan Peterson’s Understanding Exposure. When you learn how to control aperture, shutter, and ISO settings you can make many more creative choices in your photography, and you also can figure out why your shots may be coming out under or over-exposed.
I’ve written one how-to article on MUO about using different aperture and shutter speeds with a 35mm camera. There are several other similar articles on the Internet that provide similar exposure exercises and techniques.
But if you’re an iPhone or iPod touch user, you might want to check out two free apps that aim to illustrate how aperture and shutter settings work. Of course, these free apps try to wet your appetite for the full paid version, but if you’re interested in understanding the subject, you might as well take advantage of the free versions, and if you find them useful, try the full versions.
The apps were designed by two photographers, Alexnder Ketko and Chris McCarthy, of Islap101. Their two free lite versions are called Photo Module 1: Aperture, and Photo Module 2: Shutter.
Each app is divided into lessons and recipes. The lessons use an interactive button to simulate actual lens settings for aperture and shutter speeds. For example, when you move the button up or down on the aperture module, it shows how the lens opens and closes down, like in a real camera. A similar lesson shows how aperture settings will affect say a landscape shot, whereby the smaller the aperture speed, the sharper the depth of field for a landscape shot.
Likewise, Module 2, illustrates how fast and slow shutter speeds open and close the shutter on a camera. The interactive lesson on this module would have been better though if they had simulated the sound a shutter makes at fast and slow speeds. The shutter of course sounds slower when it’s at lower shutter speeds, and often times that’s why your photos may be coming out blurry, because the shutter speed is too slow.
The next lesson on the shutter module shows how different shutter speeds will freeze or blur a moving subject in a shot. This is where understanding shutter speed provides you more creative control over these types of shots you make with moving subjects.
Each module also includes Recipes which are one or two paragraph instructions for taking shots using the lessons taught in the module. Some of the recipes are illustrated with actual photographs.
These apps alone may not help you to fully understand exposure settings, but they have the right idea. The interactive lessons give you a sort of hands on understanding of the subjects. But it’s only when you take what you learn from the modules and try those similar shots on your camera that you really start learning how to shoot in advance shooting modes on your camera.
One last tip I would give you for understanding camera exposure settings is to get a fast lens for your camera, such a very affordable 50mm f/1.4 lens. This lens will open wide enough to get a great shallow depth of field portrait shots, which will in turn illustrate very quickly the effect a large aperture has on the foreground and background of a subject. A wider aperture blurs the background and sharpens the foreground in a photograph, which is the least you should know.
Let us know how you learned to shoot beyond automatic mode on your camera. Do you find the subject of exposure difficult to understand? Don’t be shy, you’re not alone. See if these two apps might help.