are almost always easier to print than negatives with a little less exposure.
In particularly tricky lighting, such as hard-to-capture low light, you might
even partially bracket in one direction two or three times—by increasing exposure
one stop, then increasing it again by two or more stops.
Bracketing works best for still subjects; candid or moving subjects usually
will not sit still long enough to maintain the exact same framing in all your
brackets (although if you use autobracketing you can get off three shots very
quickly). At any rate, it’s best not to use bracketing as a crutch. Learn to expose
film correctly and confidently, and then bracket only those very tough exposure
situations or critically important subjects, for which you must make absolutely
sure you have a good exposure.
Expose for the shadows and compensate. For precise exposure control, take a
meter reading in the darkest part of the scene in which you want to render good
detail. Once you’ve made the reading, adjust the f-stop and shutter speed to let
less light in by one or two stops—to guarantee the shadows will be rendered
black, not middle gray.
For example, if your portrait subject has a black sweater, point your meter so
it only reads light reflecting from the sweater. To do this, move your camera or
handheld light meter close to the sweater to take the reading. Suppose the meter
suggests a reading of f/2.8 at 1/60. If the sweater is fairly dark, adjust the f-stop
and shutter speed combination so it allows in one stop less light, such as f/4 at
1/60 or f/2.8 at 1/125. If the sweater is very dark, reduce exposure from the recommended
reading by two stops to f/5.6 at 1/60, f/4 at 1/125, or f/2.8 at 1/250.
The logic is the same as when taking a general reading of a scene with mostly
dark areas. When you read light from dark areas, the meter suggests an f-stop
and shutter speed that produces middle-gray tones, not darks. Decreasing the
exposure will make these areas lighter (less dense) in the negative and darker
(denser) on the print.
This exposure strategy is based on an old photographic adage:
Expose for the shadows.
By guaranteeing that the dark areas of your scene have good exposure, all the
other areas should be adequately exposed. This strategy is really a strippeddown
variation of the Zone System, a sophisticated exposure and film development
system popularized by the legendary photographer Ansel Adams in the
1930s. Among other Zone System tenets is this one: the very darkest important
areas of a scene should measure two stops darker than middle gray, so require
two stops less exposure than a meter reading suggests. It follows that if the
dark areas are not extremely dark, one stop less exposure should be adequate.
Incorrect film exposure can occur for a variety of reasons. Sometimes your
equipment might need repair; for instance, the shutter speed might be inaccurate
or the meter might need adjustment. Other times, user error is the problem;
perhaps you’ve made a mistake in metering your subject or setting the camera
controls. But there are many situations when incorrect exposure occurs even
though the camera and meter are working fine and you seem to be doing everything
right. It’s important to understand these problematic situations, so when
you encounter one—and you will from time to time—you can use the meter intelligently,
rather than relying on it absolutely. Here are some common exposure
problems and suggested solutions.
Backlighting. A scene is effectively backlit any time the light behind the subject
is brighter than the light in front. Backlighting, one of the trickiest and most
common exposure problems, causes the foreground subject to render too dark
and sometimes as a silhouette.
If you take a picture of a backlit subject without adjusting the meter’s suggested
exposure, the overall scene may be well exposed, but the foreground
might lack adequate exposure. This is because the foreground is darker than
the background and will reflect less light back to the film. Thus the foreground
will be rendered too light (clear) on the negative and too dark when printed.
Sometimes backlighting creates an interesting silhouette or evocative mood,
but most often it causes disappointment, because you lack good detail in the
most important part of the scene.
The classic backlit situation occurs when the sun is shining at the back of
your subject and toward the camera. To avoid this, make sure the sun lights
your subject adequately from the front or side. However, backlit situations are
not always obvious, and they don’t always happen when the sun is out. If the
scene includes a lot of bright sky, your subject may be effectively backlit, with
the bulk of the light coming from the sky—located behind the subject and not
falling on it. A similar situation may occur indoors when your subject is positioned
in front of a window.
The simplest way to handle a backlit subject is to give the film more exposure
than the meter recommends. This will produce a darker negative overall, which
will produce more density and thus better better detail in the subject area. The
amount of extra exposure needed depends on how backlit the subject is. Generally
you will need to add one or more stops—perhaps one stop if the backlight
is subtle, two stops if it is more evident, and as much as three or more stops if
it is severe.
Start by taking a meter reading of the entire scene. If the meter recommends
an exposure of f/11 at 1/125, use f/8 at 1/125 or f/5.6 at 1/125 instead —or an
equivalent combination to add more light. While adding exposure in this way
will produce better detail in your backlit subjects, it also will cause the lightest
areas of your subject (sky, window light, and so forth) to become even brighter.
In some cases they will become so bright that they may be rendered with little
or no detail in the negative and subsequent print. As discussed later, reducing
the developing time when processing film can help correct this problem by keeping
the highlight (light) areas from becoming too dense.
Another method of dealing with backlighting is to walk right up to the main
subject to take your meter reading, or use a spot meter reading, so you will be
measuring only the light reflected from the subject—not the light reflected from
the brighter background. In any autoexposure mode, use AE lock to hold that
exposure, then move back and take your picture. Or, set the f-stop and shutter
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