Silhouettes demonstrate how awesome it can be to occasionally break the "rules" of photography. It's pretty easy to photograph a silhouette--many new photographers do it all the time. They just don't always do it on purpose. Recently, I told you about "Five Common Photo Mistakes." This week, we'll intentionally commit the first mistake--underexposing your subject--for some creative effects.
Choose the Right Subject
What should you silhouette? Given the right lighting conditions, you can turn almost anything into a silhouette, but not every subject will look good as a shadow. Remember that a silhouette lacks detail--it's just an outline filled in with black. Consequently, you should look for subjects with strong, recognizable shapes. A complex, busy subject might not work, especially if you need to see details to make sense of it.
Configure Your Camera
You can get good results with any camera and any kind of exposure control.
First, turn off your camera's flash. We don't want to throw any light on the front of your subject.
Next, set the exposure mode. There's no need to get fancy; you can leave your camera in its automatic mode. We want to take advantage of your camera's exposure lock feature, though. As you might know, virtually all digital cameras lock the exposure setting when you press the shutter release button halfway down. This allows you to point the camera where you want to the exposure to be measured, lock in the exposure, and then reposition the camera to fine-tune the composition. See "Focusing When Your Subject Isn't in the Center" for more about that.
What if your camera doesn't have an exposure lock feature? Then you can try using exposure compensation instead. Take the picture normally, but set the camera's exposure compensation (usually abbreviated as EV) to -2 or -3. That will underexpose the photo, hopefully rendering the subject a deep black in the process. You might need to experiment with a few different variations to get the right effect. For more information about using this setting, refer to "Fix Your Exposure Before You Take the Photo."
Keep the Subject in Focus
Of course, you'll also want to keep the focus in mind. For best results, we want the subject in sharp focus. If your subject is far enough away, that's not a problem, since when you lock the exposure on the background, it'll set the focus to infinity, and you'll get good results. But if the subject is too close, it'll be in a different focal range than the background, and your silhouette will be fuzzy.
The solution? Check your camera to see if there's a way to lock the exposure and focus separately. If there is, use that mode to prevent the focus from locking in on the background when you set the exposure. If that's not possible, switch your camera to manual focus and focus on the subject by hand. It's not as convenient as automatic focusing, but it'll make a big difference in your photo.
Take the Photo
Now it's go time. The easiest way to photograph a silhouette is to position yourself so that the subject is between you and a bright background, such as the sky or bright artificial lights.
Point the camera directly into the brightest part of the scene and depress your camera's shutter release enough to lock in the exposure. Then, keeping our finger on the partially depressed shutter release, recompose your picture and shoot.
If all goes well, you'll get an inky-black subject, since the exposure was based on the brighter background. If your subject isn't quite silhouetted, you can try again, underexposing the image even more using the exposure compensation control on your camera. In the photo linked here, I silhouetted a child against the sunset.
And in this photo, I spied a bird that simply would not wait for me to walk around the tree for better lighting.