Note - larger copies of the photos in this post are available by clicking on the photo.
I've decided to write a series of three posts on backlighting, frontlighting, and sidelighting in nature photography. As you might have guessed, this is all about the direction of light. When taking a photo, you should always be thinking about the direction of the light that is illuminating the subject. Is it coming from behind you, from the side, from behind the subject or somewhere in between? Different subjects and situations call for different lighting direction. By setting lights and placing a subject, a studio photographer has a great deal of control over the direction of his light. A nature photographer has some control over sunlighting by planning ahead before going to a location. Often we just have to take what mother nature dishes out.
Backlighting is when the light in a photo comes from behind an object. This can be a tricky situation to handle, but when done right can produce some very dramatic photographic compositions. With a back lit subject you must pay attention to the exposure. Manipulating the exposure can dramatically change the photo.
In this first backlight example the rising sun is behind the boat and I have set my exposure for the light of the sunrise in the clouds and on the ocean. Because of the brightness of the sunrise and clouds, the boat and the bird are dramatically underexposed. In fact, they are silhouettes with almost no detail. If I exposed to see the details in the boat, the sky would be very over exposed or blown out with no details. This is one of those situations where you're not going to capture the entire range of light without an advanced technique, such as HDR.
Sometimes when shooting into the sun you can create a sunburst or star effect by stopping down your aperture to a small opening such as f16 or f22. In the photo of Crabtree Falls I used the leaves in the trees to block some of the sunlight so that it didn't overpower and cause the falls, rocks and trees to be under exposed. The trees were blowing in the wind and I took several shots to get one with the star effect but not too much light.
You have to be careful when shooting into the sun. If the sun shines directly on the front of the lens you can get lens flare which will show up as spots or circles on your image. Use a lens hood or other object to shade the front of the lens to avoid flare.
The lightsource is not always going to be visible in a backlit situation. This can make the dynamic range of light smaller and the photograph easier to expose correctly. The subject is still backlit which can give you a very cool photo.
In the first example with the Great Blue Heron (I am calling this one "Fire Beak"), the sunlight is on the back side of the bird and is not lighting the side of the bird facing the camera. Where the light shines through the feathers and beak it makes them appear to glow. Photographing a person in these conditions can make their hair glow, almost like a halo.
In the second example, the sun is shining through the tulip, making the entire flower glow like a lightbulb. Because the flower is very bright with the sunlight shining though, the background is dark making the flower stand out even more.
Finally, you may be able to use your flash to compensate for a backlit situation. In the photo of June and I, I intentionally positioned the camera to create a backlit situation so that the sun was shining through the leaves making the most of the fall colors. Without a flash, either June and I would be underexposed or the leaves would be overexposed and I would have lost all those beautiful fall colors. I used my flash to add some fill light to us in the foreground so that the photo was more evenly lit. You might need to experiment a little with different flash settings. I turned the flash down 1/3 EV so that we weren't too light compared to the background leaves.
I hope this short explanation of backlighting has been useful to you. If you have any questions, please drop me a note or give me a call. If you know of others who might enjoy these posts, please let them know about the blog.
I'll be talking about front lighting and sidelighting in future posts.
The Eastman Camera Club is running a monthly challenge and the theme for February is "Sweet Tooth". I had to come up with something to show for this month's challenge so I looked around home to see what I could come up with. We had four Hersey Kisses left. Add a mirror, some Rain-X and some water drops, and you come out with something like this.
I was using a 100mm macro lens and shooting from about 10 inches above the drops. When I moved closer to the drops the depth of field became so small that it was almost impossible to keep the entire drop in focus. 
