Coming away with good photos is always a challenge when traveling. After all, you can't really come back when the light is fantastic, not every time, and need to work with what nature provides. And if that is back lit, then silhouettes may be the answer. You've probably taken a few silhouettes either intentionally or by mistake, like when trying for a portrait with the sun in front of you rather than behind you. The results can be fantastic, but that usually only happens when the silhouette photo is intentional. Here are the guidelines to tame silhouette photography.
Back light your subject
This simply means that the main light, usually the sun, needs to be behind your subject rather than over your shoulder. If it's a portrait, put your subject right in front of the sun, or a light source like a street lamp.
Try to use a fairly fast shutter speed, and meter off either the sky or the most brightly lit part of your scene. Then re-frame the photo with your subject between you and the light.
Use the background for metering
As mentioned, you'll need to meter off the lighter parts of the scene, often the sky. If you have a hand held meter, this is easy, but if you're relying on your camera, you'll need a 2 step process called focus lock.
Use focus lock to set exposure
To do this, but still put the subject in silhouette, point your camera against the bright parts, press the shutter half way to lock in the exposure and hold the button there. Then compose the photo like you want it, and press the shutter all the way down.
Bracket your exposure or stop down
If you're using the manual exposure mode on your camera, you can use bracketing or setting a smaller aperture to create the right combination of shutter speed and aperture opening for silhouettes. Meter off the bright part of the scene, and then take your photos with the best framing possible. Or, if your camera has Live View or similar features, adjust the settings until you see the correct exposure on your LCD.
Just get a little closer
A good piece of advice for most photo situations, but maybe even more so with silhouettes. As you want the subject to actually block your light, that gets easier the larger the subject is in your viewfinder. If you can't reposition, and the light's not quite in the right place, try to use the zoom to achieve this.
No flash please
Since the silhouette relies on the light being behind the subject, turn off your flash. Almost every camera can have its flash turned off, although the feature may be hidden deeply in the camera settings. If you don't, the camera will try to compensate for the dark subject by firing off more light. More tips on using on-camera flash.
Vary your shooting angles
Try to get a few shots in while you're at it, by covering your subject from low and high angles, and from the left and right sides too. Make your subject strike a few dramatic poses as well, like in the photo of the girl to the right. Zooming in or out will also change the whole mood of your silhouettes. And you don't need to hide your entire light source if you're shooting at the right time of day, very early or very late in the day, or with an artificial light source such as a street lamp. These light sources won't completely 'blind' your sensor by having too wide a dynamic range.
The most important tip
Just go out and shoot photos. Like any other technique, the more you practice, the better your results will be. The photos in this article are good examples of this, and are quite achievable with a bit of practice and patience.
You should follow me on twitter here.