Using A Light Meter

lights and shadows tend to balance each other out. A center-weighted meter usually works better, because the main subject tends to be near the center of the frame. A spot meter can be very useful, however, when you are photographing a scene in which the light is quite different in different parts of the picture. It can be especially useful when large areas of the picture are either very bright or very dark. When the sun is behind your subject, for example, making the sky very bright and leaving your subject in shadow, you will need to make a spot reading of the subject to be sure that it is correctly exposed.

Fortunately, there's an easy way to do this, even without a spot-meter. Simply move close enough so your subject fills most of the frame. Then step back and compose your shot, setting the exposure as indicated by your close-up reading. Some cameras permit you to "lock" the exposure where you want it by pressing a special button. When you use this technique, be sure that you don't create any shadows on your subject when you move in for the close-up reading.

Hand-held meters read both reflected and incident light. For the reflected light reading, you aim the meter's lens at your subject, just as you would with a built-in meter. For the incident reading, you place a translucent cover over the meter's lens, stand near your subject and aim the meter toward your camera or toward the light source. If you're shooting outdoors in even light (either all sunny or all cloudy, for example), you can obtain an allpurpose average reading by taking an incident reading from the sun.

Hand-held meters have one additional advantage. If you attempt to take any photographs in very low light (at night, for example), you may discover that your camera's light meter doesn't work at all shutter speeds. It may shut off when you get down to 1 /8 of a second, perhaps, or 2 seconds. A decent hand-held meter, by contrast, will give you a reading for shutter speeds of 4 minutes or more (depending on the ISO of your film).

One final point: as noted in this chapter, reflectance light meters assume that your subject is neutral gray in tone. If you want to photograph a subject that is brighter overall (such as a snowy field) or darker overall (such as a black cat), you'll need to change the aperture accordingly. If you don't, both the snowy field and the black cat will turn out gray . . . which is probably not what you want. For the snow scene, you'll need to use a larger aperture than indicated, and for the cat you'll need to use a smaller one.

The specific gray that a light meter assumes you want is one that reflects only about 18% of the light it receives from the sun. (Pure white reflects close to 100%; pure black close to 0%.) This figure-" 18% gray" —has been scientifically calculated to represent average lighting for most scenes.

So, if the average light reaching the light meter is darker than an 18% gray, the light meter will recommend a larger aperture or a slower shutter speed, to let more light in. If the average light reaching the meter is brighter than an 18% gray, the meter will call for a smaller aperture or faster speed, to let less light in.

Nine times out of ten, this is precisely the kind of advice you want. The light meter will recommend the camera setting you'd choose yourself, if you took the time to figure it out.

Ah, but what about that one time out of ten when the light meter's advice is not what you want? Suppose you're photographing someone who is standing between you and the sun. Because the sunlight is coming right at you, it is very bright. Unless the person is filling up most of the frame, your light meter will react to the bright sunlight and tirge you to select a very small aperture or a very fast speed. What will it do to your photograph?

By letting only a little light into the camera (just enough so the sunlight shows up as a nice gray), the person you intended to photograph will look like a black blob. This is probably not the effect you hoped for.

Here's another example: You're photographing a black cat on a black couch. The average light in the scene is quite a bit darker than an 18% gray. Your light meter will tell you to use a very large aperture, or a slow shutter speed, or both. The result? A washed-out looking gray cat on a gray couch.

None of this means that a light meter is a bad thing. A light meter is a great tool. Its primary drawback is that it wants to make everything gray. Knowing this can help you use it more effectively. If you're shooting under tricky lighting conditions (any conditions in which precision is important), take a meter reading off something that is close to an 18% gray, and set your camera accordingly. Your blacks will be black, and your whites will be white. If you want to make the photograph darker or lighter than "normal," you can then adjust your aperture or shutter speed accordingly. If, for example, you decide that you'd like the whole scene to appear darker than it actually is, you can take a reading for an 18% gray and then decrease the aperture by one or two stops.

Fine, but how are you supposed to find a sample of 18% gray when you need it? You can buy a 18% gray card that is scientifically produced to be exactly 18% gray. Or you can use the gray card you already have: the palm of your hand. Whether you're black, white, hispanic or oriental, you can obtain an acceptably accurate mid-range reading simply by holding the palm of your hand in the light and aiming a meter at it.

When you do this, be sure that the lighting on your palm is the same as the lighting on the subject of your photograph. Your hand should be held so that the light strikes your palm at the same angle as it strikes

By metering off the subject's face, rather than averaging the entire scene, a rich black context was produced for this striking portrait. (Student photograph.)

your subject. Don't let the camera cast a shadow on your palm. Also be sure to hold your camera close enough to ensure that other light is not confusing the reading. Most modern cameras have center-weighted averaging meters. This means that they read light from several points around the image area, but give more importance to the reading at the center. Therefore, your palm should fill most of the image area, and should especially cover the center.

(Note: To increase the precision of your "palm readings," compare them to readings from a gray card. Place it in open shade and take a light meter reading from it. Be sure that the card fills your view-finder. Then

Shadows, produced by angled light, help to "anchor" objects so/idly as well as adding visual interest. (Student photograph by Joshua Noble.)

If you don't want a silhouette when shooting a subject against a bright sky, it is essential to meter the subject . . . not the sky. This is the sort of shot that automatic cameras tend to mess up. (Student photograph by Steve Gates.)

take a reading from your palm in the same light. The difference between the two readings indicates how far your palm varies from an 18% gray. You should add or subtract this amount whenever you take a reading off your palm. For example, if the gray card reading was f/5.6 and the reading for your palm was f/4, then you should always open your lens up one stop more than indicated by a "palm reading.")

There are more sophisticated theories and techniques for obtaining ideal lighting, but this one is certainly the easiest. Most of the time, it'll do just fine.

Another common way to avoid the pitfalls of a faulty light reading is called bracketing. When you bracket a shot, you shoot several frames at different exposures. By doing this, you are simply improving the chances of getting a correctly exposed image. If, for example, your light meter called for f/8 at 125, you might bracket by shooting one frame at that setting, plus one at f/5.6 and one at f/11. Or you might shoot five frames within that three-stop range, using the half-stop settings on your aperture ring. You can also bracket by adjusting the shutter speed. For example, f/8 at 60, 125 and 250.

Digital Cameras For Beginners

Digital Cameras For Beginners

Although we usually tend to think of the digital camera as the best thing since sliced bread, there are both pros and cons with its use. Nothing is available on the market that does not have both a good and a bad side, but the key is to weigh the good against the bad in order to come up with the best of both worlds.

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