Digital Photo Tip: Where’s the Light?
Light doesn’t just provide the photons tjay excite your camera’s digital sensor. It can reveal shape and texture or hide imperfections, depending on the angle of the source relative to the subject. Light is one of the primary tools we use as photographers, whether we’re photographing people, birds, landscapes, widgets, or plants.
While there are many variations, we can boil light direction down to just three concepts: front, back, and side lighting.
Front Light
When the light falling on a subject comes from behind the camera we call it front light because it is illuminating the part of the subject facing the camera. Front light can be at the same level as the lens, above it, or below. The most natural position is above the lens because we’re used to light sources, like the sun or a ceiling light fixture, being above us.
When front light is very close to the lens it tends to flatten the subject and hide texture. We’ve all seen photos made with an on-camera flash where there are no shadows under the nose or in the eye sockets. All parts of the subject are illuminated equally. The closer the light source is to the lens, the flatter the light falling on the subject.
Front Light on Yellow Willow
While the little flash built into most small cameras gives a horribly unflattering result, sometimes front light is appropriate. Fashion photographers use it because it hides wrinkles and pores. Nature photographers sometimes use a ring light, which surrounds the lens, to illuminate all parts of tiny subjects so heavy shadows don’t get in the way of seeing detail.
Even in sunlight, when the sun is behind the camera like in the photo of Yellow Willow above, the result is flat and not very interesting. It’s hard to see the texture in the foliage and the shrub looks like a big green blob.
Front light from below the camera is a way to induce a sense of foreboding and danger. It’s unnatural. Think scary Halloween pictures.
Side Light
When the light source is between 45° and 135° off the axis between camera and subject we call it side light. Most often side light is between 40° and 90° so it is still lighting up more of the front of the subject than the back. As with front light, side light can come from above, level with, or below the lens.
Side Light on Daffodils
Side light is my favorite kind of light for most subjects, both in the field and in the studio. I like it because it casts shadows. They’re what reveal the shape and texture in a subject. As I wrote last time, the size of the light source relative to the subject determines the softness of shadow edges. But the shape and direction of the shadows is controlled by the position of the light.
When photographing landscapes, the time of day controls the position of the sun relative to the subject. Often the most interesting light and shadows are found early in the morning or late in the afternoon. Many photographs will scout a location and determine when the sun will be in the right place to give the effect they’re after. Today, visiting a site via Google Earth makes it possible to plan ahead from your office.
The landscape at right was photographed fairly early in the morning in October, looking south with the sun coming in low in the sky from the east (camera left).
For flowers, whether in the garden or in the wild, it’s often possible to choose an individual specimen while keeping the light direction in mind. I’ll often walk around a subject to see both how the available light plays on it and how well it can be separated from the background.
Back Light
When the light is coming from behind the subject, toward the camera, we call it back light. It is illuminating the back of the subject, maybe creating a rim of light or shining through a translucent subject like leaves or petals.
Back light can be very dramatic, but you need to use it with care. Since the light is coming toward the camera it’s easy to get serious lens flare if you’re not careful. Of course, that may be the effect you’re after. One way to avoid flare is to hide the light source behind part of the subject, like a tree trunk or a person’s head.
In the photo of a columbine blossom at right, the sun is just out of frame to the left. You can see a little lens flare against the sky.
I rarely use back light by itself in my photography but it is almost always present to some degree or another. This is especially true in my portrait work where the back light helps to separate heads and clothing from the background and accents highlights in hair.
The columbine has backlight from the sun and sky coming through the blossom and a reflector bouncing light up into the flower from below.
For plants I like the look of foliage with soft back light coming through it.
Combinations
We rarely work with a single light source in a totally dark environment so front, side, and back lighting are relative and usually refer to the brightest light source striking our subject. Particularly with side and back lighting, I’ll add fill light from near the camera position to control the darkness of the shadows. Fill can come from the sky, a reflector, or another light source.
There are an almost infinite number of combinations of light you can use. The important thing is to think about the effect you’re after. If you want soft, shadowless light then front light with a big light source is the place to start. If you’re after dramatic shadows then a smaller light source placed off to the side will do the trick. Shine your light through a translucent subject to emphasize details in its structure or place your light behind a solid subject to highlight its edges.
Go play. One of the classic lighting assignments in photo classes is to place a white egg in a cup on a white background. Put your camera on a tripod and set up a simple composition. Then use a single light (a standard household bulb will do) and move it around the subject, exploring what happens.
None of this has anything to do with which camera you use, whether it’s your grandmother’s Brownie or the latest expensive digital SLR. Light is light, and that’s what takes a photograph from the mundane to the dramatic.
Hi Mark! – Always love your newsletter. I especially have enjoyed your columns on light. I was a painter for many years (before I finally accepted that I have some skill but no talent and gave all my supplies to my granddaughter who has talent and is developing skill) and have always loved the way light changes our environment. I’ve even taught my husband to “see” light! We especially love the changes in the day east of the mountains. Thanks for great entertainment.
Linda, so many people take light for granted. It’s either there or it isn’t. I’m glad you were able to teach your husband to see it. That is certainly an acquired skill, one that’s absolutely critical to any of the visual arts.