In our last post, “The 4 Advantages Of Photographic Backlighting”, we discussed how backlighting helps control contrast in a scene, creates beautiful rim lighting effects, enhances color of translucent subjects and helps models relax in front of the camera by eliminating the need to squint into the sun. In this post, we’ll go over some of the pitfalls of backlighting and how to work around them.
Camera metering is the first issue, and it can be a bit tricky. Placing the sun behind your subject can fool your camera into thinking there is more light on your main subject than there really is and causing it to underexpose. It’s all that light flooding around the sides of your subject. The trick is to either move closer to your foreground subject or zoom in so that no backlight shines on the front element of your lens. Fill the frame with your subject, blocking out direct sunlight, and take a meter reading. Move back to your original position, recompose and shoot using the same exposure. Your camera will probably be shouting at you that you are overexposing, but just ignore that. This technique guarantees that the shadow side of your subject is properly exposed.
Metering is much trickier when photographing backlit translucent subjects. In the case of wildflower petals, fall leaves or colorful sailboat spinnakers, you must override your meter and overexpose the subject. Don’t hesitate to open up, or overexpose, one to two stops to correct for the backlighting. It all depends on how translucent your subject is. Watch your histogram and push the highlights right to the edge of clipping.
The second hurdle is to block direct sunlight from hitting the front element of your lens during exposure. Sun bouncing around inside your lens creates flair, a kind of fog that degrades contrast, color and detail in an image. It can also appear as spots of light, depending on the aperture setting for that exposure. Generally you want to avoid flair, but there are times when the effects of flair can be used to create a type of hazy atmosphere—a warm summer day kind of feel.
The easiest way to avoid flair is to place your subject directly in front of the light source. Blocking or diffusing the light reduces the intensity and cuts out flair. A subject can also be positioned so that the sun is in a quarter backlit position, either to the right or left behind your subject. In this case, the lens shade that comes with a lens will often do the job of blocking direct sunlight, keeping an image flair-free. When shooting landscapes with my camera mounted on a tripod, a hat or a gray card often does a great job of shading my lens.
One of my first lenses was an ancient Kodak Ektar, mounted on a 4×5 camera, that exploded with flair any time the sun was positioned even slightly in front of the camera. Modern lenses have coated elements that eliminate a lot of flair, but not that Ektar. It was a curse, but I quickly got expert at shading my lens during exposure. The beauty of backlit images quickly made up for the hassle of working with that lens.
Controlling contrast, adding golden rim light and increasing color saturation all guarantee that your backlit photographs will be the most dramatic images of the day. Give it a try, but watch that flair!