Beginning photographers are often instructed to shy away from photographing backlit subjects. The classic stereotyped message they’re told is to shoot with the sun behind their back so the subject is front lit. While this holds validity in that it’s easy to obtain a proper exposure, the light is flat and lacks interest.
Backlight is so much more intriguing and exciting. The purpose of photographing a backlit subject is to make it glow as the subject is rim lit in a halo of luminance. If the subject possesses translucent qualities, the effect is enhanced as it appears to be lit from within. Another purpose is to silhouette the subject to emphasize its shape and form. Make sure the background is strong, simple and has a lot of color, and allows the viewer to focus on the outlined subject.
Challenges — Exposure and Flare
Exposure: If capturing a silhouette is the primary focus of the image, take a meter reading from the area behind the subject. In the accompanying image of the backlit avocet, I simply took a reading off the water in an area where no glare reflected off its surface. I locked that exposure into the camera by pressing half way down on the shutter, recomposed the image and then made the picture. In a situation where the silhouetted subject comprises a large portion of the frame, the above technique becomes imperative or else the image will be overexposed. The camera reads the large black silhouette and thinks it needs to open up the exposure. The result is a gray silhouette with an overexposed background. When in doubt, bracket the exposure or simply use minus compensation.
Flare: If the sun shines directly into the lens, the chance of getting flare is greatly increased. I recommend you remove any filter as it adds an additional glass layer that can bounce light. Press the depth of field preview button to stop the lens down. If flare is present, it will be seen. If it is, carefully place a shadow across the front of the lens with your hand, a hat, newspaper, etc. The trick is to create a shadow across the front element without getting that item in the photograph. If possible, find an element in the composition that minimizes the potential and place the sun behind it as in the accompanying photo of the Three Sisters formation in Monument Valley. Stop the lens down to ƒ22 and let the sun slightly poke its head out from behind the object hiding it. A sun star will be the result. Practice positioning the sun to create the best possible star. Every lens will behave differently and produce a different effect.