The Role Of Ambient Light
The light in our world greatly influences how we feel, act, and think. The same is true of the light in our photographs. Whether natural or created, the look of ambient light can be a powerful communication tool. Likewise, it can be an unwanted part of the scene we want to photograph.
Sources Of Ambient Light
Ambient light is everywhere. It is the light that you find in the scene already. There's a huge range of ambient light sources that you can use either in or as a light source for your photographs: the sun, fluorescent lights in a grocery store, the lamp on a bedside table, car headlights, or a cake covered in birthday candles.
While most ambient light comes from continuous sources, you can also find ambient light from intermittent sources. The blinking lights on roadside construction barricades, a strobe light in a modern dance performance, and the bulbs that appear to race around a marquee in Time Square also provide ambient light.
The Clues Of Ambient Light
Ambient light goes a long way toward informing your viewer about the feeling and time of your photograph. So knowing the look of ambient light enables you as a Speedliter to create a feeling in your photographs—even when the light you need isn't present.
Through our own experiences, we associate certain emotions with different types of ambient light. A smiling child lit by morning light streaming in through a window suggests comfort. A couple lit by the glow of candlelight suggests romance. The beam of a flashlight cutting into a dark cave creates a sense of suspense. A lone figure lit overhead by a street lamp portrays a sense of loneliness or foreboding. A pair of bright lights heading straight at us suggests panic.
Just as ambient light provides clues to the emotion of a photograph, it can also tell the viewer much about the time of day in the photograph. Long shadows and a warm cast to sunlight indicate that it is either early morning or late afternoon. Conversely, steep shadows in brilliant light indicate that it's noon. A warmly lit room interior with only black in the windows tells us that it is night.
Ambient Light Does Not Always Appear Ambient
As your skills as a Speedliter develop, you'll come to understand that ambient light does not always have to be the key light (a.k.a. "main source") in your photo. In a portrait session outdoors, you can position your subject so that the noon sun falls on her back and shoulders to create a rim or separation light and use Speedlites as the key light.
In the first of the two photos opposite, we can see that the noon sun was lighting the subject frontally, meaning that it was at my back during the shoot. The combination is perfectly lousy. The shadows are steep. My subject squints his eyes. There is no clean separation between my subject and the background.
In the second image, we switched positions so that now the sun was coming over his shoulders. To create this shot, I used a pair of Speedlites—one as a key light and the other as a fill light.
When shooting toward a light source, it's important that the front of the lens is shaded. I used both my lens hood and a separate flag on a lightweight stand to prevent stray light from entering the lens.
Ambient Light Is Not Always Wanted
As much as ambient light can create a sense of emotion or time in a photograph, there will be times when you have to shoot with ambient light that is totally counter to your desired end. This is an opportunity to—dare I say—let your skills as a Speedliter shine.
Consider the situation of having to photograph a suspense writer for a magazine cover, and the only time that he is available during a book tour stop is 15 minutes during the afternoon. The photo editor for the magazine doesn't care about the challenges imposed by the author's schedule; his job as photo editor is to obtain photographs that support the article. My job as the photographer is to deliver the photographs that I've been hired to create.
As you can see in Figure 4.2, there's hardly anything suspenseful about photographing an author in broad daylight. Sure it's a portrait of the author—but not one that conveys his dark persona.
It's up to me to create a quality of light that conveys the author's persona. By using high-speed sync, a technique that we'll discuss at length in Chapter 22, Dimming The Sun, I used my Speedlites to dim the sun and effectively shoot night at noon. I think you'll agree that the portrait in Figure 4.3 fits the subject's persona as a mystery writer.
Don't worry about how I made this shot. For now, just know that as Speedliters we don't have to accept the ambient light at all.
Figure 4.2 This is how the camera wanted to record the ambient light in the scene. In order to preserve the highlights created by the late afternoon sun, the camera let the shadows go dark.
Figure 4.3 By using two bare Speedlites in high-speed sync, I was able to significantly underexpose the ambient sunlight by shooting at 1/1000 —effectively turning noon to night and creating a portrait that fits the subject's persona as a writer of suspense novels. This exposure (1/1000, f/8, ISO 100) was 2.5 stops darker than the exposure used in Figure 4.2.