Monday, July 19, 2010

The best light available – in a flash

Low light? No problem - usually. Available light can be beautiful.
We photogs are always thinking about light. I posted, a while back, about the interplay between light and shadow, and how it can make or break a photograph. Some photographers simply have a gift for seeing light and using it to create a special quality to their photographs. Sebastiao Salgado is one of those that comes to mind. He always shoots in black and white, but the light is one of the first qualities that jumps out at you. And it's always available, existing light, sometimes in conditions where some of us would just give up and not even bother to shoot. It's truly a gift to be able to see like that.
I'm a big proponent of available light photography and it's usually how I approach most assignments. By using available light, I can operate less obtrusively. It allows me to become more of a fly on the wall instead of being the center of attention. It's also a challenge, both technically and creatively, to figure out how to use available light to your story-telling advantage. Fortunately, today's latest professional level digital cameras are much more sensitive to light and create higher quality results than even the most sensitive film. (Sorry point-and-shoot owners. These low-light advantages don't yet extend to inexpensive consumer cameras due to 1) cost, and 2) the laws of physics. If you're interested in the technical reasons, try this link: What Is... ISO)
But the amount of light isn't the only consideration. First, there's the quality of the light. Is it hard, creating contrast and deep shadow areas? Or is it soft, with little or no shadows or contrast? You have to consider the direction your subject is being illuminated from: are any shadows working for you or against you? Sometimes the color of the light is a consideration, especially when you have mixed light sources, such as direct sunlight, shade, incandescent light bulbs, or florescent lights. They all have a different hue, and that can cause problems when they are mixed together.
Flash allowed me to make a better portrait by
    filling in ugly mid-day shadows and cleaning
    up a busy background.
So what do I do when the quantity and quality of light are working against me? I gotta break out the flash. I have mixed feelings about flash photography. As I mentioned before, I prefer to work unobtrusively and fade into the background. I feel the pictures that result from this approach and the moments they depict are more honest. Sometimes, I worry about altering the existing scene by introducing artificial light. However, in the interest of professionalism, particular assignments or subjects (often portraits) simply call for some lighting help.
I have a great admiration for photographers who are masters of lighting their subjects. Like I said, light can make or break a photograph, and some photographers are extremely creative in the way they use flash. One of my favorites is Joe McNally, because his background is in photojournalism and the way he works and lights his subjects is closer to what I do than many of the fashion and portrait photographers famous for the look of their images.
W. Eugene Smith (whose quote is the inspiration for the name of this blog) was known for his dramatic use of available light in his photographs. But everything isn't always as it seems. Once, when asked by a student if available light was the best kind of light, Smith responded
"Available light is any damn light that is available! "
 Indeed, Smith often had to augment the existing light by stringing up flood lights due to the lack of film sensitivity in his day. However, once the lights were up, his subjects went about their lives as though they (the lights and Smith) weren't even there.
Unless I'm making a portrait that requires some measure of direction, I try to take the same approach as Smith when introducing flash to a scene.
Unlike commercial photographers who often use powerful studio strobes to drown out existing light, photojournalists usually try to keep their equipment to a minimum and are more interested in balancing flash with the existing light. There are two basic approaches to accomplishing this.

Using flash as fill
Mid-day sun needs help.
You may be familiar with the term fill flash. Essentially, it's using flash to reduce the amount of contrast between the highlights and shadows in a scene. With today's digital cameras, it's a fairly easy operation. Expose for your scene highlights, and the camera will automatically determine how much flash is needed to fill in the shadows. This is especially useful outdoors at mid-day or indoors when the main source of light is overhead. Light from above is notorious for creating deep shadows in the eye sockets and under the nose. You can overdo fill flash. Too much, and your scene looks unnatural. But a subtle use of fill flash can open up those faces in the shadows. 
Fill-flash saves the day.
Even basic consumer point-and-shoot cameras are capable of pretty decent fill flash results, and I would recommend using fill flash outdoors during the middle of the day. Just find out how to take your flash out of the automatic mode, turn it on, and let your camera do the work. You might be surprised at how a little fill flash can really make your photos pop!

Using available light as fill
Sometimes, your light levels are just too low and you need some help to make publishable images. In these cases, the flash becomes your main light. However, you still have to balance it with the existing light unless you want your subjects floating in space. In essence, your existing light become the fill. When using this approach, the best results are achieved if you can get your flash off the camera. On-camera flash produces flat light. You lose any sense of shape and three-dimensionality. Most camera manufacturers make sync cords that maintain full exposure functionality so you can hold the flash off to the side or place it on a light stand. Those cords can be unwieldy, however. My trusty Nikon Speedlight offers an additional option - wireless flash. Thanks to the folks at Nikon and their Creative Lighting System (CLS), I can place my flash almost anywhere and still maintain full control right from the camera. It's a great option to add natural looking light from nearly any direction.

One flash with diffuser dome, camera left, on a stand about 10 feet high, fired wirelessly, creates a soft-but directional light. With the existing light used as a fill, it creates a nice, natural three-dimensional look.
Unbalanced flash = lost in space

Off-camera flash isn't an option for most point-and-shoot cameras. And at low light levels, the built-in flash often overwhelms any ambient light. You've probably seen the results: faces floating in space. Many consumer cameras have a flash mode often referred to as "slow." If your camera has this mode, it will utilize slower shutter speeds to better balance the flash with the available light. You might get a little image blur in the background at times, but try it and see if you like the results.

One more tip - soften it up
Most natural sources of light bounce all over the place, reflecting off of many surfaces, producing a softening or diffusing effect. A bare electronic flash tube creates extremely hard light from a small source. That combination is undesirable because it typically produces a harsh, unnatural quality of light with ugly shadows. There are many tricks to make the light from your electronic flash appear more natural. 
If your flash head can tilt and swivel, you can point it towards the ceiling or a wall. This is referred to as bounce flash(Gotta give Canon and their tutorials a little love, too) The resulting light will bounce off the surface, producing a much softer, broader light for a more natural look. However, light bounced off the ceiling will still produce the same undesirable shadows as any light source from above, only softer and less contrasty. To combat that, you can attach a "bounce card" to your flash to redirect some of the light forward to fill in the shadows. There are many commercially produced bounce devices, but anything with a white surface will work – even a piece of paper.
Another approach is to diffuse the light by putting something white and translucent in front of the flash to soften and spread out the light. (Don't cover your lens, though!) Again, there are many commercial products that can accomplish this, but you can use anything that's handy, in a pinch. My flash shipped with a white, plastic translucent dome that fits right over the flash head. It diffuses light forward and to the sides. If I tilt the flash head upwards, the light goes in all directions, giving me the benefits of both diffusion and bounce flash. It's about as natural and soft as as you can get from a small light source. In fact, it almost never comes off my flash.
Putting it all together: flash with a dome diffuser bounced off the ceiling and balanced with existing light allowed me to capture a story-telling moment in dim lighting conditions.

Diffusion and bounce flash are problematic for point-and-shoot cameras. Most of their built-in flashes are fixed and very close to the lens. About the only advice I have for you is to try this: Do-It-Yourself - Ten-Second Flash Diffusion. Let me know if it works!

In the end ...
Electronic flash is just another tool in the arsenal. The main objective is still to tell stories, share moments, and make connections.  Personally, I'll take the golden glow of evening light that Mother Nature graces us with over anything artificial. (The light at dawn is amazing, too, but anyone who knows me understands that it's going to take a significant assignment for this night owl to roll out of bed in those wee hours.)
Anyway, I'm done with this lighting tutorial. There are numerous resources by those more knowledgeable and talented than I. For more reading on flash photography, try these blogs:

Strobist by David Hobby

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