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THE ANSWER MAN:
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Let's face it--the world isn't built for the convenience of the
photographer. We've all been to a location with a fine composition
right in front of us, but the light makes the contrasts too extreme
for us to capture it with the camera.
The technlogy of photography, film or digital, has its limitations, and one of the biggest is dealing with a limited ability to capture a range of tones, compared to the infinite variety of light we actually see in nature. Ansel Adams developed his Zone System of exposure and development specifically in response to this challenge. It allowed him better control over transplanting real-world contrasts into the limited contrast range of film and prints.
You don't have to learn the Zone System to deal with lighting extremes today. While there are a number of possibilities available to the photographer, I've chosen two techniques that will help: filters and flash.
Filters Still Work In The Digital Age
With the advent of digital, some photographers have begun to believe the computer can do anything, including eliminate the need for filters. Of course, the traditional photographer who never uses a computer will find some advantages to using filters, but even the digital-savy photographer should have some filters in his or her camera bag.
While the computer can do a lot, especially with the two-three exposure
system of tonal range control, it has limitations. If you can control
the tonality of your photo while actually photographing the subject,
you'll have less work to do later in the computer. And for some
scenes, with respect to HDR (High Dynamic Range) software, it's easier
to be sure you've captured the tonalities with which you need to
work in one exposure than trying to make multiple photographs work
together later.
The key filter every photographer should own is a graduated neutral-density filter (also called graduated ND, grads and splilt neutral-density or ND filters). It's a huge advantage to the photographer who wants to get the best exposure from an extreme situation.
Many of you know and use this filter, but for the beginner, here's
a quick explanation. The graduated neutral-density filter is clear
in one half and gray (neutral density) in the other. The two areas
blend together in a gradation of tone in the middle of the filter.
The filter rotates inside its mount, allowing you to move the dark
neutral-density area over the bright part of the scene. The clear
half of the filter now sits over the darker part of the scene. The
result is that the darker part of the scene comes through directly
to the sensor, while the brighter part is dimmed by the ND filter.
The blending in the middle hides the change. This allows you to
capture a scene with a greater range of brightness than could be
handled normally.
The most common way of using this filter is with landscapes. The sky is frequently much brighter than the land, making photos look unnatural compared to what we see with our eyes. With a grad, you move the ND portion over the sky so that its brightness is dimmed, allowing the sky to better balance with the ground. If your filter is of the screw-in type, you're limited to rotating the filter, which may or may not match your actual scene. With rectangular filters, you can slide them up and down and rotate them in their mount to better match the horizon.
The late Galen Rowell was a master of using the graduated ND filter in the landscape. Look at any of his photos and you'll see rich colors in both the sky and ground, usually impossible to achieve with a straightforward shot of the scene. He'd even put multiple filters together to intensify their effect, moving them slightly to be sure the blended areas fit the scene. Graduated ND filters come in a variety of strengths that affect the intensity of the effect as well. The most common are one-and two-stop neutral densities; the dark areas of the filter (the neutral-density part) will knock down the brighter parts of the scene by one or two stops. If you were to buy only one, I'd recommend the two-stop model, as it will work on more extreme conditions. The more expensive graduated filters tend to give you the most neutral density in the dark part of the filter, which can help keep your colors clean.
In addition, graduated filters also come in colors (usually in one-and
two-stop strengths). These can be used to both reduce the brightness
of an area and enhance the colors. For example, a blue grad can
be used when the sky is a washed-out blue; it will darken and increase
the color of the sky. An orange or tobacco color grad can intensify
a sunrise or sunset.
Graduated filters don't have to be reserved for the sky; they can be used for any situation where the lighting conrast is high. Examples include putting the ND section over intense snow next to a pine forest, using the dark part of the filter to knock down the sun's reflections in water, or moving the ND area over the brightest part of a slot canyon. No matter how you use them, these filters help you to compose a photograph that just won't happen any other way.
How to expose? Most of the time, you can use your evaluative or matrix-type metering system and you'll get a decent exposure. Bracketing can help, and, of course, wtih a digital camera, you can check to be sure you got the right exposure on your LCD monitor.
Beyond that, the best thing to do is get out and experiment. This is one filter that I always keep with me, even now that I shoot digital. It's so easy to use that it's worth a try in many situations where you have extreme brightness conditions.
Try Your Flash To Subdue Hard Shadows
Fill-flash does exactly what the technique's name suggests--it fills
your subject's shadows with light from a flash unit. Without a fill
light, shadows in high-contrast situations would record as empty
black holes. In the past, fill-flash was considered a professional
technique because of the complexity of the technical issues involved,
but modern photographic equipment has made it simple for everyone.
Your equipment will calculate exposure for two light sources, your
flash and the ambient light, and arrive at settings that balance
the two. Fill flash works well for objects within a moderate range
(you might light a boulder or a small tree, but not a canyon or a
mountain). More powerful, accessory flash gives more options for
fill-flash. For dramatic photos, use flash at sunset to fill in
the immediate foreground to balance the glowing sky.
You can start using this technique with any camera that has a built-in
flash. If you're using a compact digital camera, go through your
camera's flash modes until you get to the flash-on setting (the name
changes, depending on camera model). The setting will cause your
flash to fire even though there's plenty of light to make the photo
without it. If your camera offers Scene modes, you also can try "Slow
Sync" or "Night Portrait."
Some dSLR cameras also have built-in flash. Popping up the flash tells the camera you'd like to use it, and your camera will work the flash into it's exposure calculations automatically. Generally, little more is required from you when it's bright outside.
When the ambient light becomes dimmer, your camera may keep the shutter speeds in a hand-holdable range for some modes, which will allow the background to go dark. The fix depends on the camera; for many, you can use shutter-priority auto-exposure and set a slow shutter speed for the dimmer ambient conditions. Some cameras will keep giving proper ambient light exposures when you choose aperture-priority exposure. Slow-Sync and Night Portrait settings are sometimes available on these cameras and will often balance ambient and flash light quite well.
The big limitation of built-in flash is low power, which can be
a real problem outdoors. Today's dedicated hot-shoe flashes communicate
with your camera, providing automatic operation like built-in flashes,
yet offer considerably more strength to balance bright light. With
the use of special connection cords, they also can be placed off-camera
for spotlighting and other effects. Placed away from the lens-to-subject
axis, their light creates texture and form that can be interesting.
You do have to consider how much fill flash you want. If the light outside is coming from behind your subject, creating a silhouette, give your flash the full normal exposure.
If sunlight is falling directly on your subject, causing small pockets of shadows, then filling in the shadows completely will ruin the three-dimensional quality of the light. Try reducing your flash's output by one stop. This dimmer fill still opens up the shadows so they don't record as empty black pockets, but preserves the character of the lighting. For more dramatic results with even less fill, try -11/2 or -2 stops.
Your camera's metering system may well give you nicely balanced
light automatically. Experiment beforehand so you'll develop a feel
for how evrything works. When using digital, rely on your camera's
LCD monitor to double-check that your camera's settings give you
a balance of light that you like.
Keep the range of your flash in mind. The range varies according to model, but in bright sunlight, assume it's no more than 5-15 feet for most built-in flash units, with the more powerful hot-shoe-mounted strobes reaching perhaps 20 or more feet. For all flash units, the fill range increases as the amount of sunlight decreases (it's easier for the flash to match the lower light level), so you'll have a better fill-flash range as sunset approaches.
If you shoot with a telephoto lens, some of the flash beam is wasted as it spreads out to cover the field of a wide-angle lens. Many hot-shoe-mounted flash units have a zoom system that extends flash range by concentrating the beam into a telephoto's narrower field. For very long telephotos, 300mm or longer, aftermarket Fresnel condensing lenses are available to fit over the front of your external flash. The Better Beamer flash extender (which is lightweight and folds flat for easy carrying) will both focus your flash's zoom head and can extend flash range by more than 200%.
As always, you can contact me at ijschneller@msn.com.
Your comments and questions are always welcome.
